This works pretty well, I feel like if a child is small enough they could force their way under but my almost 2 year old won’t be able to do that. (Plus younger babies probably don’t have the dexterity) puppies however, if small enough will zoom right under. They do have a single reinforcer thing this is cool, but for such a wide ability I’d say 2-3 would be minimum need for a puppy. I only dropped one star because I bought two and one came clearly used, so there is definitely a lack of quality control there…
Erin 
