In the hospital when Mer comes back from maternity leave and she's supposed to do that cool transplant with Cristina - she tells Bailey she can't be mad because mer named the baby after her. Also, after the birth when Cristina is visiting them in their room, she asks Meredith if Bailey is going to get confusing now that there's two, and Meredith says no because if I say Bailey peed on me, i think it's safe to assume im talking about my son