Congrats on the new puppy!
Like the others have said, I really think it is a case of puppy see, puppy do when there are other dogs in the household.
We had just been in our new house for a year when we got Preston last Nov. My hubby did NOT want another dog, as he did not want a puppy having accidents all over the new carpet. I was pretty worried about it also, especially when I started reading how hard Yorkies were to train. All in all, Preston was much easier to train than any dog we ever had. I think he just watched the other two, and when they never got in trouble for going outside, but he was given a stern OUTSIDE for going inside, he decided he liked their way better. HA HA
I would just try moving the pads toward the door, or even putting one outside and taking him to it frequently, he will catch on pretty quick.
__________________  Preston  and Paisley have stolen my  |