Where do they wander to?

Yesterday when I went to get the car from the garage for our early morning appointment, Oscar was by the front door but no Tammy in sight.  Told him he would have to wait until we came back so I could feed him.

When we got home there was still no Tammy.  Fixed breakfast for mother and then went outside to feed the dogs.  That is when I saw Tammy curled up asleep by a fallen tree with Oscar near by.  Had she been here all the time and I just did not see her?

She blends in so well with the surroundings.

When they finally woke up, they ate well, slept some more and once again disappeared into the night.  They showed up this evening for dinner and once again took off.  Where do they wander to?