Remember Michonne got all weirded out about the baby earlier. There was blood on the carrier. Beth had no blood on her. He kills were long distance. Michonne had blood on her hands from killing the Govenor as well as from helping Rick. The only other individual with blood on them was Daryl, and he left with Beth. Shasa was with Bob and Maggie she did have blood on her from Bob getting shot but they took off with out the baby. I think its the logical conclusion.