Would she be able to respond to him at all if he was say, trying to get her attention, or try to get her to move or pet him? I ask because my male is cuddly and if he is on the bed, he will nudge me for attention, or to move if I am in his way and if I don’t respond, he’ll nip because that is just rabbit for “Hey, over here” or “Hey, get out of my way” and he has left bruises on my foot before if I didn’t move it. They don’t realize we don’t have fur to protect us like a bunny would and need trained to realize nipping humans that way isn’t OK.
If his testicles have descended, he may be older than you think. The vet will be able to tell you. In the mean time… if he has been with your doe at all and she is not spayed, she could be pregnant. It only takes mounting her for about a second to impregnate her, rabbits do it quickly. If the vet thinks he is old enough to neuter, you may want to think about getting her done first just in case. For one, a male keeps viable sperm for up to 4 weeks after neutering, so less risk of an oops litter if she’s spayed.
I would certainly not leave him alone with your daughter though. A young, hormonal bunny can leave scars on even adults, so it’s best to keep them away from small children that can’t defend themselves. He will still be hormonal up to a month after his neuter, then should begin to settle down and be trainable.