A user recently decided to take to Reddit’s AITA forum for perspective on an alleged family conflict. The post states the dispute traces back roughly two years, when the couple’s daughter had bloodwork done and her blood type didn’t match either parent’s. Her husband, per her account, initially suspected infidelity, a reaction she descried as understandable given his position at the time, since their daughter also has physical features neither parent could immediately trace. AITA for telling my husband to get over “being cucked by his twin” byu/Beautiful_Common_940 inAITA_Relationships To settle the question, the couple decided to do the wise thing and wait on the result of a paternity test. The results showed the man tested was not, in the strict biological sense, the girl’s father. The test pointed to someone who shared more than half of her DNA. That’s a level of relation that’s apparently associated with a parent or full sibling rather than an uncle. Since the husband was raised as an only child and his father had died. Years earlier, the family had no immediate explanation. That was until his mother eventually told the couple he had a twin brother in the womb whom he, uh, absorbed before birth. “And so I guess my husband’s testes are his twin brothers,” she wrote. The husband grew worried about his legacy The husband has struggled to accept what the test found, telling his wife their children aren’t biologically his and that he’d never have what he called a “real legacy.” An argument over the matter ended with him leaving to stay at his mother’s house. The poster said her own mother later called urging her to be more sensitive to his feelings. Now before we get into the internet’s verdict, you must have questions, so let’s talk about the science behind this. A rare but medically recognized condition Absorbing a twin in utero is linked to a rare medical condition called chimerism. A person with chimerism carries two genetically distinct sets of cells in their body. The condition traces back to vanishing twin syndrome. Early in a multiple pregnancy, one fetus can die and be reabsorbed by its surviving twin, passing along a second set of genetic material in the process. (per Healthline) A 2017 case study in the Journal of Assisted Reproduction and Genetics described a father from Washington whose paternity turned up the same way, not designating him as the biological parent. Researchers traced the mismatch to sperm carrying his twin’s DNA instead of his own. That was the first documented case of its kind. Barry Starr, who worked on that case, told BuzzFeed News that “even geneticists are blown away by this.” As for the Reddit post in question, the poster later gave an update saying that the husband now wants to “look into other options and try for another child.” The consensus, on the /AITA_Relationships repost thread, is overwhelmingly NTA. “OMG, tell him to grow up,” one user replied. “What’s so special about you that your genes have to be passed on?” “I would not be having another child with him with the purpose being to have one DNA matched to him,” another reply read. “What if he treats his non DNA related kids differently?” “Good grief! Of all the things to be upset about! NTA,” added another. “NTA and your husband is ridiculous,” RickRussellTX wrote. “It IS his child, and his DNA. He just has two sets.” As of her latest update, the two had not reached a decision on a path forward.