Bright-eyed and bushy-tailed comes direct and intact from the classic Fox Hunt. A fox with dull or cloudy eyes or a limp, listless ungroomed tail is one in poor health and will not provide a good...
Two bushy tailed rodents include the dormice and squirrel.
squirrel, raccoon
A metaphor for a bright smile, is the sun. A smile can brighten up a persons day, and so can the sun (:
Pie