Babtism

My SOs mother is putting the pressure on for baptizing baby. It’s my SOs 3rd child and my first. His first two were baptized. I was not, I’m not against it but I feel like it should be my sons choice when he’s older. I told her I am undecided at this point and I already feel bad and don’t want him different then his siblings But also don’t feel like I should be pressured. Thoughts?