They get more problematical as they get older.

Come to think of it, the same is true of humans. Take Amos, for instance. When still a young man he was charming, presentable, courteous, and honest...but what a change the years have wrought! (Or should I say "rot"?) He is now a pathological liar, a rumourmongering political dirty trickster, a character assassin, a dipsomaniacal voyeur, and a dabbler in cross-species sexual liasons of the lowest sort. If he were someone's pet, I'm afraid there would only be one solution at this point....