What goes up a hill with 3 legs and comes back with 2?

A person walking using crutches, holding up his hurt leg. (3 legs) He stays with his sister at the top of the hill until he heals and doesn't need the crutches. He walks back down with 2 legs.

Variant of A young man goes up the hill on 2 legs, and then later as an old man with a cane he comes down the hill.