I have nearly 5 1/2 month old springer cross terrier who has been very good at house training, until last few days. After a couple of weeks without cleaning up an occasional accident in house she has suddenly started weeing in house all the time. This evening she got on sofa and weed on there! 
She has also had a few snaps and growls from the older dog recently, for no obvious reason. Any thoughts on why this is happening? Could she be getting hormonal in a coming into season way? I have not changed routine, she still gets lots of praise and treats for peeing in garden, and I am cleaning up with bio washing solution so no smells.