Welcome to Yorkie Talk and congratulation on your new addition! What is his name?
Transitioning to a new home can disrupt eating and potty habits. Is he eating the same food that he had in his last home? Sudden changes in food can cause diarrhea.
Was he potty trained/crate trained in his previous home? Does he appear to do okay with the crate?
I would try increasing the number of potty breaks (trips outdoors) and try keeping him out longer. Are you walking him or letting him out in a yard? Sometimes walking will speed things along.
Each dog has his or her own body rhythm that will determine how often they need to go. My boys are the same size as your baby. My older boy poops twice a day, my younger boy goes at least 3 times a day. They are pad trained and pee a lot, probably for the rewards. They know how to exploit the system.
Some dogs will only poop once a day.