I took Carrie's conversation with Saul at the end of the episode to mean that she thinks her sister is right. She's coming to terms with the fact that she's not a fit mother and the kid would be better off with the sister and her husband and she's going to let it happen because she can't stop being a spy. It's basically impossible to be a CIA agent and have any kind of a normal family life. That's why unlike most employers, the CIA actually encourages their agents to marry one another because there is zero chance for a successful long-term relationship with a civilian, let alone raising kids.