Sounds like a
bicycle wheel
My adventurous owners keep one on the ground
Wheelie!

But two is more common, most people have found
Standard way of riding is with two wheels on the ground
Three is the usual for those young of heart
Tricycles for the kids!
And four is for those learning the part
A bicycle with training wheels.

I have a cousin who uses one more
Though one of them is not like the other four
Hmm....this thing?!

or, more probably
Your cousin is a car (another common mode of transportation) and the 5th wheel is the steering wheel (thanks, @Neon612!).
What the OP intended before seeing the other 5-wheeled bike above:

Title: And it goes around
They sure do.