I don't know the full story just read this post, I personally wouldn't allow your dog around your children! He obviously has issues and your putting your children in a position they will never thank you for nor will your dog. I would provide a safe area your dog to sleep in away from the kids, not giving him free rein, restricting him to an area that you know he can be happy and stress free in and your children can do as they wish- possibly the kitchen/a crate (start crate training as if he's 8 weeks) living arrangements need to be modified, your children should never be at risk of a bite in their own home! Sadly sounds like the dog rules the roost so to speak hence the current issues.
I hope you find someone suitable to take him.
He doesn't have "free rein", he is in the living room with me, along the hall and into the kitchen when I go. We have panels coming out of our ears here, stopping him from going upstairs/in other downstairs rooms but I can't tell when one of them may want come downstairs and I'm in the kitchen with him or to come into the living room. I did crate train from 8 weeks old and he spent his time screaming, barking and howling, as well as toileting in there so had to abandon it. I've brought it out again and he still does the same thing (I know how to crate train, I done it with my previous cocker).
What is the point of having a family dog if he has to be kept away at all times. What happens when we want to go out together? It's just not normal for any of us and I can guarantee if I start limiting where he can go further, he'll be even more stressed out as he detests not being by my side.
He doesn't rule the roost but we are seriously limited in our family life because of him. We make him sit before going out of a doorway (me first), he walks to heel, has loose lead time, then heel time as advised by our trainer and isn't allowed on furniture. However, he is incredibly stubborn and hyper and because of this, when he starts his hyper spinning and barking, no command will get him to stop (even the trainer couldn't offer advice on this one, said he'd eventually calm down if I followed his training plan - he hasn't).
lescef - the vet didn't offer any suggestions regarding medication, I do have him on calming supplement powders but as yet, they don't seem to be working.
I will contact Dog's Trust but would be sceptical given his behaviour, they'd be happy to rehome him, I'd feel awful if he bit someone else, it's bad enough dealing with the guilt I have over my daughter.