Episode: Season 15, Episode 11
What happens: Meredith has just as many daddy problems as mommy ones. Because Thatcher is never around for much of her life, Meredith has always been frosty toward her biological father. (It doesn't help that he slaps her when his wife dies.) In season 15, Richard reveals to Mer that Thatcher is in hospice for leukemia. When Meredith finally visits him, he's basically on his deathbed. He passes away after the two of them talk about Meredith's children.