You are really good at being "cute". Nobody else can stop you two from having a baby. Never heard of having a baby would be illegal. Child born in Canada has citizenship by birth. However, the parents would not be granted the permanent residency or citizenship by giving birth to babies in Canada, but that does not seem to pose a risk at keeping the whole family intact---you can take your baby back to China or elsewhere so long as you act as good parents.
If you are ready(mentally, financially or otherwise) to have babies, it's a wonderful thing to expand the family. However, if your purpose of having a baby is to facilitate your own immigration case, it might be a very bad idea as it's not fair for your offsprings and that approach may not work any way.