I have always, always lived with Jack Russell's, and they are great dogs.
However, I would be very careful with them with children. The JR we have just now, and the previous one, are/were both exceptionally good with children, but young children still do not like them. Ours tend to jump up because they are small, and young children are scared of that. They are terriers, so you must be sensible with them, and that means you have to be careful 24/7. I do have a scar where I was bitten by my grandmother's JR when I was 18months old.
Might have puppies in a year or so- but nothing just now!
Beth