When did you KNOW you were done having kids?

I have a son and a baby girl on the way. Before having our son, my husband and I always talked about having 4 children. We loved the idea of a big family. Now that I’m more than halfway done with this pregnancy and it’s all sinking in, we have both been talking about having two and being done. I think three would be my absolute maximum. I’m just curious when those who are done having kids knew for sure you didn’t want more? When we are done, my husband wants to get a vasectomy. I honestly just don’t think I can handle more than two children. I don’t want my time to be divided so much and I want to be able to spoil my kids as much as possible. I think two is the perfect number. Especially having one of each. But I feel like once this baby is born, I’ll want more. When will I know I’m done?