I found out recently that there was plans for a season 4 of Animals of Farthing Wood.
In it, Fox was supposed to have grown very old, and by the seventh episode, died of old age. According to the timeline on the Farthing Wood forum, Fox is atleast 11, and by season 4 he would be 12. That's four years longer than a normal fox even lives. Even thought I would be expecting this, I wouldn't ever want Fox to die. He is the only character that is in every episode, bad enough having Bold die.

EDIT: All the episodes can be viewed in high quality
here.