I figured that out a while ago that's why :/

On two feet. Then at the end of the day, near the end of their life, they use a cane to help them walk.

Human. When a baby is born, it is only able to move on its hands and feet, which would count as four feet. Then in the day, middle age, they walk normally

YES a baby crawls on four legs a man walks on two and an old man uses a cane!

Or man