I am firmly in the belief that there is no such thing as a 'bad' dog just bad management. I've had dogs all my life. My parents bred & showed English Setters. In my time I've had German Pointers, rescued greyhound, a Great Dane & a rescued Mastiff as well as a couple of rescued Shih Tzus - they were the most challenging that I ever had to train!.
Since then I have settled on Cocker Spaniels - lovely friendly family dogs - they enjoy a good walk, love people - often bringing a 'present' of a dog toy, shoe or whatever for all visitors. My current dog once grabbed a bra from the laundry basket to greet the postman with. 😂
When my son was young he was taught how to manage the dogs - never to disturb them when sleeping, never to surprise them etc, when very young only allowed to pet dog when I was holding the dog. NEVER in the same room without me or another adult present. However, not difficult as Spaniels famously greedy & bonded with owner/mummy & would rather be with them in the kitchen (where there may be food available) or following the 'food provider' around the house just in case food will appear LOL! I'm not able to go to the loo without dog following me & trying to get onto my lap. 😂
I am always aware that dogs are not humans & need to be very carefully supervised & managed when with young children. When young, my grandchildren were taught not to pet the dog without an adult holding the dog. It doesn't matter how friendly the dog is (all my dogs were/are very calm & friendly) you can't account for the child moving suddenly, grabbing an ear or doing something that may frighten the dog & cause them to snap.
Having said that, I wouldn't have put my child into a care setting where there was a dog - too risky as you don't know how the dog's owner is managing the contact.