A few days after the call from Tommy, Becca gets another call from him. He said that his mother would visit to bring Arthur to stay at home. Becca immediately stocked up on milk for Arthur as he would be away from Arthur for a few days.
Maybe because Tommy knew that Becca had difficulty taking care of her own child, therefore Tommy tried to divide the tasks even though Becca didn't ask him to. In fact, Becca was happy because she could be free from taking care of Arthur.
While preparing Arthur's equipment, Becca is talking to Nora. He said that maybe after Tommy, Arthur would stay at his mother's house. Of course Nora was pleased to hear the news. He never minded if Arthur was with him.
An hour later, his cell phone rang. Lily called him that he was already in the lobby of his apartment. Becca did tell her where she lived because this was only for the children, so they could freely meet Arthur.