@yingtai This is such an awesome idea! When I was raising my lab from a pup many years ago, I followed the great guidance of Ian Dunbar on raising dogs, and one critical thing he taught was to expose puppies to as many different stimuli as possible before they reach the fear phase of development. He included a checklist of things to try to find…we had a blast trying to find all different types of people, sounds, places. We even had a puppy party to have people over. Was so helpful!