Question: when does snow white find out emma is her daughter

title: Mary Margaret Blanchard
text: In Storybrooke , she appears as Mary Margaret Blanchard , Henry Mills ' fourth grade teacher at Storybrooke Elementary School . As a part - time volunteer at the General Hospital , she awakens David Nolan ( Prince Charming ) from his coma , and the pair gradually fall in love , despite David 's marriage to Kathryn Nolan ( Princess Abigail ) . Beginning a secret relationship , the affair becomes public and David 's marriage breaks down . Mary Margaret becomes an outcast in the town , and is arrested for Kathryn 's `` murder '' after fake evidence is discovered . Kathryn is later found alive , though Mary Margaret 's relationship with David becomes strained as he did not believe her innocence . He decides to leave Storybrooke , but the two are reunited when the curse is broken , and they regain their memories .