BUT...

Please dont worry about the Pit bull in him.Yes they can be aggressive with other animals.If they are raised right,socialized with other dogs/animals,socialized with people and children,you pup should turn out wonderful.
Don't worry??? I am not so sure. You do need to worry, not only about Pits but any large breed which has shown aggressive tendencies when you have small children. You are being given good advice with regard to socialization and training classes, but you need to continue to be on guard and attentive. Children will be children and no matter how much you educate them about proper interaction and behavior with your dog, they will invariably pull his hair, ears or tail. They will try and take or give food to him. They may want to snuggle (when he doesn't) and they are prone to hitting when they are nipped or growled at! Big dogs (especially tose with aggressive natures) don't take much to being hit by smaller creatures. So watch both your dog and your children as they grow and mature.

It's not the breed's fault it has a bad rap, it's the fault of the irresponsible owners that don't train and socialize their dogs.
No, it usually is not. And yes, irresponsible owners are by far our biggest problem. But you cannot ignore the fact that certain breeds are stronger and more apt to defend themselves or even attack. There is a reason for this. Genetically, they were bred with a guard dog in mind. A dog emerging in their bloodline who just loved everyone and licked strangers and ran around in circles, happily and excitedly peeing himself when burglars entered his home, would quickly be neutered with hopes that his genes would be weeded out. So don't take lightly the fact that a Pit is extremely strong and his jaws can crush a skull or bite off fingers. YES, I know it's not their fault, but when something bad happens, does it really matter who's at fault.

You mention that your dog was a rescue pet. With this in mind, you do not know his ancestry, his parents or would type of lineage he has. Poor Breeding can also contribute to a dog's aggressive nature.

A few years back, my brother-in-law adopted a Rotweiler. It wasn't a very friendly dog from the beginning - and I think he thought that was kind of cool. Sort of made him tough through his dog. One day the dog bit my 8 year old nephew. Everyone in the family was so upset, except my brother-in-law, who blamed my nephew. A few weeks later, he attacked him in the hallway, biting his face and ripping off his lip. Some hundred stitches later, my brother-in-law still maintained that it was Johny's fault. He must have done something to provoke the dog. My husband got on the phone with my sister and told her, "he was coming over there". I don't know what he would have done, because when my husband got there., the dog and my brother-in-law were gone. Neither one of them has returned to the house since.

So, my point is this. Don't just accept the fact that "all dogs are great". Yes, most are. But because of poor breeding and bad training, some can be and are dangerous. Again, you are doing the right things and are getting good advice, but don't be simply cavalier about it all. Remember that your dog will be big and you children are small. Just keep an eye out for any warning sign should they emerge!