My mum and dad have 2 dogs, one is large and bumbling and the worst he is capable of is pinching the sock off my baby's foot so gently he doesn't even notice. also, a 9yo yorkie x collie (seriously  ). she's about 6kg but she's very collie like in her behaviour and frankly, quite neurotic and can be snappy with other dogs, and she was recently attacked and injured quite seriously which has made her even more highly strung although physically she's fine now. she is however nothing but sweet and highly obsequious to all humans. she had often been the target of toddlers when out and about as she's little and fluffy and she's gentle and calm never any issues whatsoever. (she is 99% on the lead due to ring unpredictability with dogs who she thinks might like her stick/ball)
my baby is now 7mo and is very keen to explore. yesterday, she growled at him as she had a ball and he was coming in her direction. so nobody needs to tell me she needs to be PTS, rehomed etc as that is absolutely NA. she's never going to be left alone with him, he is always accompanied/supervises, she has plenty of baby free space (big house, 24/7 garden access) and she is a valuable member of the family.
what i would really appreciate is some common sense advice on how i can train her to understand he's not another dog, or cat, he's a human and therefore not a threat to her. she's never really known a child before (only those we pass by on walks) and she finds the whole thing a bit worrying.