They can go in with you and hold them or show you tamer dogs. You need to take your kids with you when you go. Also if you have other pets..schedule a date and time for them to meet any possible new family member. They also let you take them home for a test run if all is good.
I wouldn't bring him. Some of the dogs can be excitable, jump etc. just wanting to play. It would be better for you to meet the dogs first and see if there is one that you feel would be okay with your son.
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