Your thieving friend could be a she & maybe she is having her babies in that nice soft plush filler she took out of your cushion. Those squirrels know how to live I tell you.

I use to take two teaspoons & fill them with peanut butter & sit on a lawn chair in my folks back yard. The squirrels would climb up on the lawn chair & sit on the arm of the chair & eat peanut butter off the spoons. One time I had two on each arm of the chair eating peanut butter. They would get a little greedy & you know how sticky peanut butter is & they didn't have anything to wash it down so they would gag on the peanut butter if they took to much at a time. I would start giggling & the chair would be moving but they would keep eating.