Kitten crying every time he uses the litter box.

I have a kitten, he will be 13 weeks old on Sun, he cries (meows very loudly) every time he uses the litter box.  He doesn't cry when he actually goes to the bathroom ... just when he paws around and digs.  Anyone have any idea as to why he does this?  His mom runs over when he does it and just watches him.  Thanks

Is this with poo or pee?  Does the poo look normal.  Some kittens will cry because they are just not sure what to do.  However, if he sounds like he is crying in pain, then a vet check is a must for UTI.

All my kittens announce they are using the litter tray, meowing as the dig then quiet while they actually go.

He doesn't cry like he is in pain.  He just ... meows while he is digging.  lol  Thanks!