My female mini schnauser is 1 year old and has been potty trained to go outside, for the past 2 weeks she has been going in the house, sometimes it seems like she is scared to go outside, nothing has happened to cause this. We also have her 6 month old sister who has no problem going outside, do I have to retrain her?

Is it possible that something DID happen to cause this, especially if you let the dogs out into your yard without being right there with them? Even a bee sting, a loud noise, an animal, a sharp object in a paw, anything. Just take both dogs out together a few times a day for a while, soothe her, hold her, praise her when she goes. Do you live in the north where it's getting colder, and could she be super sensitive to it?

Call a veterinarian. When you have an animal that is your responsibility,