I definalty don't have all the answers BUT I raised a cleft baby. She is a Chihuahua, not a yorkie. And I never bred her mom again. There were 4 pups in the litter and she was the only one born with a cleft.
It was a fight, but "we" made it
She'll be 2 in July and she's the love of my life
Here are some pics to show you how much smaller she was from her littermates.