XAVIER / MARKO FAMILY TREE
The earliest known relatives of the Xavier family were the Graymalkins. The Graymalkins lived approximately 200 years ago in what is today Westchester County in upstate New York. Charles and Martha Graymalkin had one son, Jonas. When Jonas was 16 years of age, his father Charles discovered his nascent homosexuality when he found him with another boy. Calling him an abomination, Charles entered a fury and beat his son so severely that he buried him on his property, assuming that he was dead. Jonas had survived, however, thanks to his mutant powers activating due to ordeal. As his powers grant him invulnerability and regenerative powers in the absence of light, being underground saved his life and placed him in hibernation. He remained there until his resting place was disturbed two centuries later and he was found by the students of his “descendant” Charles Xavier. As Jonas is a relation of Charles Xavier and is said to have been the only son of his parents, it seems likely that the common ancestor of Charles Xavier was a sister of Jonas. [X-Men: Manifest Destiny #3]
The Graymalkin's line did continue and must have had some significance locally in Westchester going forward, as by the modern day the “Xavier Estate” housed a large mansion on Graymalkin lane. The mansion was home to Dr. Brian Xavier and his wife Sharon. It is unclear whether it was Brian or Sharon who was descended from the Graymalkins.
Brian worked as a researcher for the Black Womb project, which was investigating mutation in children. The project was secretly run by the immortal geneticist Mr. Sinister under his guise as Dr Milbury, alongside his longtime ally, Amanda Mueller. Sinister was hoping to use the project to write his own DNA into the code of different mutant children so, in the event of his death, he would be reborn in a new host body. Essentially, he was seeking immortality. It is likely that the union of Brian and Sharon was engineered by Mr. Sinister, as an experiment as part of the Black Womb project. When Sharon later expressed reservations about the tests and experiments that “Milbury” was conducting on their son, Charles, Brian said it was what they had “signed up for.” Either way, Dr. Brian Xavier died while Charles was seven years old, killed in an alleged accident in the Black Womb project headquarters in Alamogordo, New Mexico.
That we are aware of, Sharon had one pregnancy by Brian prior to his death, twins, Charles and “Cassandra.” In what would become an ongoing pattern of violence in Charles' life, from which even the womb proved little respite, Cassandra attempted to strangle her brother with his umbilical cord. Charles protected himself by unleashing a psi-blast killing his sister. Despite the death of her physical body, Cassandra's consciousness did manage to survive, eventually crafting a body for herself before returning to plague her brother and his students in later years. In her most recent confrontation, Cassandra was forced to feel empathy for the first time by Jean Grey. Realizing that Cassandra's attempt to reform her body had been defective, Grey had nano-sentinels correct Cassandra's brain to fix the part that was responsible for her feeling empathy. Whether she can find redemption or is even interested in it, long term, remains to be seen. [New X-Men (1st series) #121, X-Men: Red (1st series) #11]
After the loss of her husband, Sharon quickly remarried widower Dr. Kurt Marko, a colleague of Brian's at the Black Womb project. Kurt brought his own son, Cain to their blended family. Cain's mother had passed when he was three years old. Cain had anger issues and was adversarial with Charles instantly. His violent streak was inherited from his father Kurt, who was abusive to all members of the family. While the marriage between Brian and Sharon may have been arranged by Mr. Sinister, the marriage between Kurt and Sharon was definitively a product of the project and was loveless. When Sharon suggested that she and Kurt take their two boys and run, Kurt violently beat her in an alcoholic rage in front of the children. Calling his new wife a “sow,” implying she was only used for breeding, he made it clear that Milbury would not allow desertion, which was why she was now “Sharon Marko.” Sharon herself passed a short time later through undisclosed means and Charles was left in the care of Kurt. [X-Men Unlimited (1st series) #12, X-Men Forever (1st series) #4, X-Men (2nd series) #12-13, X-Men Legacy (1st series) #211-214]
Cain suspected that his father had some responsibility in the death of Charles' father and goaded him about it. One day this escalated as Charles overheard and opted to confront Kurt. During the confrontation, some laboratory equipment was damaged, causing an explosion. In an uncharacteristic act of heroism, Kurt carried both Charles and Cain out of the burning building before succumbing to his injuries. Just before he died, he told Charles that, while he had not killed his father, he could have saved him and that he should beware of his brother.
The brothers' relationship remained strained as they grew to adulthood. A significant period of time had passed before they met by chance while they both were serving in the army in Korea. While they were under attack, Cain deserted their unit and Charles pursued him. Stumbling across an ancient cave, Cain discovered the gem of Cytorrak and grabbed it, despite Charles warning. This act triggered a cave-in and, though Charles managed to escape, Cain was turned into the magical mutate, the Juggernaut. [X-Men (1st series) #12] Initially a bonafide antagonist to his brother and later the X-Men, Cain has had redemptive periods and has on occasion fought on the side of the angels with his brother Charles, the two have even discussed their abusive childhood at one point. Unfortunately for Cain, he has yet to make the full journey to “Damascus” and often returns to a life of crime.[Uncanny X-Men (1st series) #429]
[Note: In the MC2 alternate timeline, Juggernaut reformation managed to stick and he married district attorney Sachi Yama. Their son Zane inherited some of his powers and later went on to join his world's Avengers becoming more of the principal characters for that universe. [J2 #1] Cain has met Sachi Yama in the main Marvel Universe but, so far, hasn’t shown any romantic interest in her. [X-Men Forever (1st series) #6]
Offspring of X
Despite his role as the symbolic “father” of the mutant race, Charles Xavier's own experience with actual fatherhood has been poor to say the least.
During his youth, Xavier worked at a hospital in Haifa, Israel and met Gabrielle Haller. The young woman had been traumatized by her experiences in the concentration camp at Dachau. Xavier used his telepathic powers to treat her and eventually he brought her out of her catatonic state. Despite Gabrielle's status as his patient and therefore any relationship between the two being highly inappropriate, Charles did opt to pursue Gabrielle. When Xavier later left Israel to continue his journeys, he had no idea that Gabrielle was pregnant with his child. Gabrielle gave birth to a boy whom she named David. Having learned of Charles' telepathic abilities, Gabrielle decided it was best to keep David a secret, as she had feared he had used his powers to influence her initial interest in him. [Note: It is likely Gabrielle's status as a Holocaust survivor may be retconned as time continues to advance.]
Gabrielle became a traveling diplomat on behalf of the state of Israel. During a trip to Paris, the Israeli embassy was attacked by a terrorist cell led by a Palestinian named Jemail Karami. A ten-year old, David was present and was luckily protected by his godfather, Daniel Shomron, but the man was killed in the crossfire. The trauma of this event unleashed David's dormant telepathic abilities and he wiped the terrorist cell, inadvertently absorbed their leader's psyche into own mind. David's psyche continued to fracture after this event and he developed new multiple personalities with distinct super human abilities. Initially, Gabrielle attempted to take care of David's degenerating mental health herself but eventually she saw no choice but to reach out to mutant specialist Dr. Moira MacTaggert, who alerted Charles Xavier. [New Mutants (1st series) #26-28]
Over the years, Charles and David have not managed to form anything that could be considered a father-son relationship, due to a succession of deaths, resurrections and breakdowns on both their parts. David's relationship with his mother has also strained over time. During a brief period, he was under the care of Dr. Moira MacTaggert it seems that David had some maternal perception of her. It is possible the reason for Charles' distance from David (and even his “bond” with Moira) may be actually be by design. In the Powers of X and House of X series, it was revealed that Moira, despite being believed a human for most of her history, was actually a mutant. Upon Moira's death, she would resurrect at the time of her conception and reset the timeline. In her most recent life, she opted to recruit Charles early in the timeline by showing him memories of all of her lives. In two of these realities, she and Charles had married and if either of them consider this relationship valid in the current timeline is unclear. As part of their early alliance, Moira's noted in her diary in Powers of X #6, that she and Charles were attempting to find “matches” so they could produce reality-altering children. David later curiously developed this power-set with a new personality in the image of his surrogate mother “Moira-X” during the Age of X event. If this is in fact the case, it seems that Charles may not be that different from his own father.
An unexpected liaison from Charles Xavier was his alleged marriage to the shape-shifting super-villain Mystique. The exact circumstances surrounding their relationship are unknown, however it did result in one child. Mystique made a decision to surrender the child for adoption in the United Kingdom immediately after giving birth, as she considered herself unfit. As she was posing as a version of Moira MacTaggert at the time, the baby boy was presumably registered as “baby MacTaggert.” In one alternate timeline, a version of the child grew to adulthood in an adoptive family. He was also named Charles and it is possible Mystique stipulated this as part of his adoption. His adoptive mother may have been a mutant herself (displaying minor telekinetic abilities). As a teen, he accidentally killed her when his burgeoning telepathic manifested. Figuring out his true identity, he sought out his biological mother on the island of Madripoor, only to discover that she had been killed and usurped by his younger half-brother, Raze. The two brothers decided to band together and formed a version of the Brotherhood of Mutants in their timeline, eventually leading their team to the past to fight the X-Men. After one of his schemes had nearly destabilized the whole timeline, he was seemingly killed by Magneto as punishment alongside his team. What has become of his infant counterpart has yet to be revealed. He may have been erased as "collateral damage" when Tempus and Professor X travelled back in time to prevent the birth of the omega level mutant, Matthew Malloy. [All-New X-Men (1st series) #27, X-Men: Blue #20, Uncanny X-Men (3rd series) #23-31]
Charles' next foray into fatherhood was even stranger than the others, as it not only managed to occur with an extraterrestrial but also posthumously. During a period in which he was “dead,” Charles’ DNA was crossbred with his also deceased paramour, Lilandra, former empress of the Shi'ar Empire. The girl, Xandra, was rapidly aged and has inherited Charles' telepathic powers. Despite her youth, she has ascended to the throne of the Shi'ar Empire. [Mr. and Mrs. X #1-5, New Mutants (4th series) #2-7] Xandra violently proved to be eligible for Krakoan resurrection protocols when she was killed by agents of the Kin Crimson, then projected her mind across light-years of space to her father's Cerebro unit. Charles ensured the resurrection of his daughter through the Five. [X-Men: Red (2nd series) #4, Marauders (2nd series) #3-5]