When Mother's Day arrived without any sort of message or visit from Achilles, Thetis was disappointed, but not really surprised. She knew Achilles didn't think too much of her right now, so she wasn't expecting much.
So when the knock came, she was curious as to who it might be. But when she opened it and saw Patroclus on the other side, she couldn't help but smile. "Well isn't this a nice surprise," she said, stepping back to let him inside. "Please, come in."