Conversation so far:
How old was Lionel Barrymore when he started acting on stage?
Lionel Barrymore appeared in a stage production at the age of 15.
What was the name of the play Lionel Barrymore was in when he was fifteen?
Lionel Barrymore appeared in a stage production of The Rivals at the age of 15.

Question: Did he perform with any relatives like his parents who were actors?
Self-contained rewrite: Did Lionel Barrymore perform with any relatives like his parents who were actors?