Thanks @nikv for the 'Tennyson' quote, I tend to agree.
I had a couple of young possums coming through my pet door to warm up by the radiator a couple of winters ago😎 They probably learned the maneuver from my cat friends. They also stole the cat food, so I had to stop leaving it down at night.
Surprisingly, the cats didn't seem to mind them scurrying along in the yard or porch from the time they first appeared as babies (the size of small rats)
As they grew, the possums would fight each other; I guess a territorial thing? One buried, I had found dead in the yard, another one had gotten hit by a car and a police officer shot it to end it's suffering.
Good of you to be kind to the possums, so many are not. We don't have them here but I have read that they eat large numbers of ticks. That makes them very useful critters in the larger scheme of things