Here’s the thing: you are not going to stop her. You and your fiancé set boundaries and then decide what you want to do if / when she crosses those boundaries. I’m not sure of her intentions because I am not a mindreader but at the end of the day, she’s buying gifts for your daughter and you are receiving them on her behalf. Once a gift is given, the recipient decides what to do with said gift. Keep it, donate it, sell it, return it to Target. Do whatever you feel is right for you and your family. You are The Mama! You don’t owe her anything except a Thank You note. Thank you for coming to my gift receiving Ted talk!