::polishes little horns:: Glad to have cheered up your day.

knowing Harriet she probably just told him to get lost and let her get on with it
Canonically, he spends the entire time of Baby 1 cleaning silver in the basement as displacement activity. I imagine Peter would be very useful attending the labour of someone he cared nothing about, and completely hopeless in the case of Harriet, when he would be in a corner gibbering "She's going to die and it's all my fault".