No word on whether they're connected to the battle yet. "AN ANTONIO (AP) — THE remains of three people were found at the Alamo amid an archaeological exploration ahead of planned renovations at the site of one of the most famous battles in American history, state officials said. The remains of an infant, a teenager or young adult, and an adult were found during archaeological exploration in Alamo church's monks burial room and nave, the Texas General Land Office said in a news release Friday." www.usnews.com/news/us/articles/2019-12-14/remains-of-3-people-found-during-renovations-at-the-alamo
The mission building was there at least 100 years before the battle, and before that stone structure was built there was a wooden or adobe structure, although I don't recall when that was built. It would seem doubtful given the circumstances after the fight, that anyone from the battle was buried in the mission itself. .