Some may disagree with me but small dogs and small kids generally do NOT go hand in hand.
Small breeds can be 'nippy' and are more easily injured by a little one who may 'sit' on the dog.
Teaching children to respect the dog BEFORE you bring it into the home is a good way to start. Use a stuffed dog toy and pretend that it's a new dog you just brought home. Teach the children to be mindful of where the dog is, not to hit, sit on, slap or rush towards the dog. Show them how to approach the dog and how to gently pat the dog. If you do not know these techniques yourself, I suggest you learn or ask here
on this forum.
So, what do you think about the teaching aspect before you get the dog?
The dog should also have it's own 'place' to go to away from the children and they should know 'not' to bother doggie while he's there. IE his dog bed in a corner/crate.