Pup forgets poop training

My pug Queenie gave birth to two lovely pugs four months ago. She's been a great mom to both puppies, teaching them a lot of things including where to poop. It was great that we didn't have to go through the same toilet training routine we had with Queenie. My brother was impressed and he liked the pups' temperament, too. I gave him one pup while I kept the other. Problem was, though he basically placed a lookalike litter box on his yard, his pup just won't move there and would poop anywhere. Is this a normal behavior that will pass? Or have the pup completely lost what he has learned from his mother?

 

You lost me as cute puppies, and my mind ran away with that picture of puppies

I guess if he can catch them in the act, just pick them up and put them in litter box over and over again until they got the idea. I suppose the puppies are just testing their limits and freedom, just like a child wants to explore their world.

Would love to see a picture of the puppies

 

I think that puppy needs to be re-oriented with his toilet manners. From what I understand with the pooping of dogs, they are searching for a particular odor which they may have gotten used to when they were born. So maybe you can give your brother your old litter box so the separated puppy can go back to his orientation with the particular odor.

 

You need to teach good manners suited to him.