Growling in a young dog would either mean one of two things, the first is your dog just doesn't like kids, which is possible. The second, and this can be common to spaniels for some reason, is that it's a dominance issue. I'd go with the second perso...

Labs, regardless of color, are great dogs. They're friendly, eager to please, reliable, good with kids, obedient, easy to train. Labs are the most popular breed in the US by far, in the AKC alone, labs registry numbers are around 150,000 dogs total. ...