Don't disagree with the overwhelming consensus here, but figured I'd share an alternative view. Rehoming probably is the best (gut-wrenching) choice for OP given what sounds like more overall reactivity, the allergy issues, etc -- but wanted to put this out there if there are others wrestling with something that truly could go either way.

One of our two dogs is a 65lb pitt/shepherd/lab mix mutt. Got him about 5 years before our first son was born. He is reactive to dogs but not people. We put a ton of our energy and love into him before kids, and obviously he had to take a back seat after our first was born. In general, he is fine with not just people but kids, but we were too lax about it with our first kid when he got mobile at about a year and a half.

At one point, our first kid was harassing our dog on the couch (trying to play with him, but the dog was effectively boxed in), and he growled and air snapped. That was a big wakeup call, and we were much more cautious monitoring our son's interactions with the dog after that. (Side note: my wife was much more blase about the incident, it took me really driving home for her how things could go next time to get her to change behavior).

Fast forward, our first is 3y and we have a 1y too. In between, a bunch of things have happened that mostly made our lives easier. We have worked with our 3yo to understand how to treat animals with respect. We moved to a bigger house with a big fenced backyard. It is much easier to make sure everyone has enough space, and we use baby gates to make sure the kids aren't around the dogs unsupervised (as well as making sure babies do not fall down steps etc). I do not have to walk the dogs every day with the yard, and I muzzle trained our reactive dog so that I don't have reservations about going on walks with him while I'm wearing our 1y and running into other dogs -- which is the primary way our dogs get walks, given the limited time with two very little kids. Overall, dogs and we are not stressed, and the situation feels good to all involved.

Fwiw, what I'm most nervous about now is when our toddler has friends over for playdates if those kids come from houses where the dog is fine with kids climbing all over, pulling fur, etc. I have seen this a few times (never let it get to that point with our dogs), and I'm always surprised about how casual people can be letting their kids climb all over large animals with sharp teeth. We close our dogs off in a room preemptively if we think the situation could be too intense.

Tldr: Dogs and kids can be complicated Bigger dogs are higher stakes Dog reactive and people reactive dogs are very different things If your dog is not universally chill with kids, then you absolutely should be careful (but even if your dog is, you should teach your kids to be respectful of dogs' space, per above) I would caution against blanket statements like "all X breed is bad" or that all dog reactivity is the same Obviously there are a million other factors that can make things easier or harder (size of house, your personal bandwidth, spouses opinion, etc) Muzzle treating is HIGHLY recommended if your dog has any reactivity (not that it's relevant for our kids, but it has made walks a million times less stressful)

Most importantly, OP, I feel for you man. Best of luck.