No the only other time she did it was with her pillow. She was "digging" the pillow like to make a bed (?) and all of a sudden she rushed down to the end of the bed and I knew something was up. So I looked and she peed on the pillow! So now that pillow and the Nyla bone are off the bed.
It just really seems weird, I don't see her squat when she did it, but she is so close to the ground I could have missed it.
Thank you all again for your help!