First off, Congrats on the new addition. And it sounds like she needed you!
I agree with some of the other posters, treat her as you would a puppy. Don't give her free rein of the whole house. Watch her like a hawk when she's with you, don't set her up to fail. Perhaps take them out, when Precious is done, come back in but don't take your eyes off Princess. Wait a minute and then take her back out by herself. It
really sounds like she's had no training and very little interaction. Perhaps she's shy about going potty with Precious around, or you watching. Boo hates it when I'm watching.
He gives me such a look with his eyes, "Momma!
Don't look at me!"
Yogi is so happy to see us when we come home that he's not at all interested in going out and pottying with the other 2. However, as soon as they come back in and the door is shut he's tinkling. So for now, we are going out into the back yard with them and stand there until he potties. He's just happy to see us and it just takes a few more minutes for him to settle down and do his business.
Get some Natures Miracle to clean the spots with so that the odor doesn't attract her back. And have a treat with you when you go out so that you can reward her immediately. If you wait until you come back in to reward then she may think the reward is for
coming in, and not for
pottying.