Episode 44 of "Bones"
s02e22 Stargazer In A Puddle

The decomposed skeleton of what appears to be a young girl is found in a grocery cart in the D.C. area. Angela's reconstruction based on the evidence reveals the face of an 80-year-old woman, not a child, but the team learns the victim actually was a 22-year-old woman with a debilitating aging disease. Brennan and Booth's investigation leads them to the victim's mother, who points a finger at a former caretaker. But without a definitive lead, the team searches to find out who would want to take this defenseless woman's life, and the case strikes an especially emotional chord with Brennan. Meanwhile, Brennan's father, Max Keenan (guest star Ryan O'Neal), reappears in Brennan's life in an attempt to make a connection with her and deliver information from her past, and she's surprised by her reaction. Hodgins and Angela walk down the aisle with Brennan and Booth as maid of honor and best man, respectively, but all does not go as planned.