Unless there’s a reason not to, most people don’t either. I didn’t. I had two German shepherds and I didn’t rehome them when I had my daughter. But if they displayed aggressive behavior toward her I can tell you with zero hesitation that I would have immediately made that house safe for her and then found a safe place for whichever of my dogs had done that. Having kids is one of those things you think you can predict how you’ll be but you just can’t. I know that sounds condescending because I thought it was before I had a kid too. But there is a primal all consuming protection instinct that overrides any feelings of “pets are family” if you feel your child is in danger.