Trying to keep Shelby quiet has been very difficult to say the least. When I go out, I have been leaving her in an x-pen so that she doesn’t try to jump up on any furniture or run around with her siblings. Sidney has been keeping her company in pen when she voluntarily goes into it. Tonight, I wanted to go out for my nightly walk and Sidney did not want to leave the pen without Shelby. I tied the ends of the of the pen and left for my walk. On a arrival home, I was greeted by Shelby and Sidney. The ends of the pen were still tied together. I had left Sophie in her crate. She is the only untrustworthy one in the group. I am clueless. How did they get out???