Hi Heather! Welcome to YT! Would love to see pics of your guys
As for the training, Yorkies are notoriously hard to potty train. I thought I had Mandie trained really early and I used to brag about it..then she fooled me. She even regressed a couple of times. I think the best thing to do is to start from square 1 with them. Crate training would be a good idea for their ages.