My 12 year old son thinks he is the owner of Buddy, the marginated tortoise, but I spend more time with him than anyone else! Buddy has already outgrown his first table and hasn't worked out that he can't get under all the furniture any more.
We keep him in the table through the day and allow access to the house when we're around. The garden is walled so we can give access, again when we are around, as we haven't plucked up the courage to leave him out through the day. The cats find him fascinating and I don't think they can hurt him, but while he is still small, better safe than sorry.
I am still very divided about hibernation.