You are brave to think of a GSD puppy with so many young children in the house! GSD puppies are more bitey than most, and we affectionately call them landsharks as they go through that phase. Their little puppy teeth are SHARP! Like needles, and pups play with their mouth, so expect scratches and bites and tears, both from you and the kids.
GSDs are very smart and active, as a dog bred to be a working dog should be - that means that their little brains are always going 100 miles per hour, and they will get into everything and anything - so they require CONSTANT supervision, and due to their puppy propensity to bite (and bite hard!), they should NEVER be left alone with little kids. In a few months puppy will be six months old, weigh 60 lbs, and will be a rambunctions ball of playful energy that can inadvertently do a lot of damage with the little ones by knocking them over and nipping - thus the constant supervision part.
The regular walks are going to be great for a GSD, but one thing that growing pups need is a lot of room and opportunity to run! Careful about having them run around with the kids though, as a herding breed, they will think that chasing little ones and nipping them is normal - again, that is where supervision and management of the pup's environment comes in to prevent these situations from happening.
Lots of info here about raising a pup - also notice all the posts about puppies that bite and people don't know what to do about it - not that much to do about it except wait for them to outgrow that phase, which can last several months.
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