We are slowly letting the older one and puppy socialize several times a day on leashes. The 20 month old has slapped the puppy once with his front paw pretty hard but no yelp from puppy(scared me more lol) and once when the 20 month old was laying on his back around the pup the puppy jumped on his belly and the 20 month old kicked him with his back leg and jumped up(I'm assuming this is fine as the older dog as in a submissive position and just letting the baby know his place). The older dog has never growled, snapped and raised hair...he is always tail wagging. Of course with the baby being 8 weeks only we will not let any off leash interaction for safety. At what age will the puppy be big enough to handle the rougher interaction with the bigger guy? We make sure we always praise the older dog for giving kisses and being so nice. My concern is would the older dog intentionally hurt the baby? He has never had socialization with other dogs as we have a senior GSD who never wanted anything to do with either of them except to try and be nasty....I totally understand this due to his age so the senior dog just kinda stays alone in the livingroom as he now has bad hips at 11 yrs old and a couple other minor health issues. My goal obviously is to make the 20 month old and the 8 week old best fur brothers. How has others dealt with the introducing, the play, etc of the adolescent dog and the baby? I want to do everything the right way from the start with no chance of injury. Thanks a bunch. I have been video watching, reading, etc but you people all seem so much more knowledgeable. Thanks in advance.