Hey, thanks everybody who chimed in with your experience! As with just about every question I ever ask, there's quite the wide variety in responses! But it all goes to help me make a more informed decision... I really appreciate it.
I think we'll let Nikko dig on blankets, but not the couch or couch cushions. The couch cushions will be the hardest part I think... They're big and soft and brown, with a dented-in big button right in the middle. I know if I ever decided to take up digging in my free time, those sure would look to me like the perfect pile of soft dirt, with a hole already started and a big button target to paw at.
Lauren & Nikko