Much has been made in recent years about having the ability for your character to be able to pet dogs in games. This evening when my Laura Bow encountered the bloodhound Beauregard lying in front of the stove. So I typed "Pet Beauregard". A box popped up that said "Okay." The Laura knelt down and petted the dog. So it is possible.

I'm not sure if the lists people have made for games where you can pet the dog go as far back at 1989, but here's on example.