honestly when it comes to kids and dogs I recommend getting a qualified, educated, experienced trainer (I always opt for the ones who use learning based theory in their training techniques) to come in the home and evaluate. Trainers are not just for serious issues or waiting to see if things "become" serious. The best time to get them in to evaluate is BEFORE things get anywhere near serious and before and incident occurs (should one occur). It's easier to address inappropriate behaviour right away in the early days than struggle as the dog makes a habit out of them and it's harder to "fix".
While it doesn't sound like Hunter is at all aggressive he is large and could accidentally hurt a child (knocking them over, loss of control in their nip and making contact). Have a trainer evaluate the situation, the household and the dog could be invaluable. ESpecially early on in the game as he's only been with you a few weeks. It sounds like prey drive and a dog that needs to learn more bite inhibition (i.e. don't nip!) It doesn't "SOUND" like a warning (But again we can't see so hard to really evaluate) and while it's normal dog behaviour, it's inappropriate.
ETA: be picky on choosing your trainer. it's a totally unregulated industry. anyone can call themselves a trainer and/or get various "qualifications" that are questionable. Personally anyone that uses the term Alpha and Dominance I would avoid but that's just me (they are out dated terms and understanding of dogs)