There's a book called "Child proofing Your Dog" that I would highly recommend.
A few years ago I brought in an adult dog into a house with a 2 year old. With very diligent supervision and training for the dog as well as the child on house manners, both learned to get along quite well.
My vet always told me to have my dogs believe the shild is a hot dog dispenser. Great treats are wonderful for intros. Over time, the hot dogs become much less and we make our kids give the dogs commands like "sit" and "down" prior to getting the treats.
Also, our dogs have "safe" places in our home where the kids are not allowed and they are allowed to retreat to if they feel the need. Under the master bed is my older dog's place and a crate In the basement is my otehr dogs spot. Kids are never allowed to go into those areas- even if the dogs aren't using them. I am, but kids are not.
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Chelle and the rest of the crew including, but not limited to Kita and Taiko (the shiba inu wrestle maniacs), Adi (reserved and dignified tabby cat), and all 28 reptiles