A secret tip

We just had to check out the sledding hill again this afternoon with
Grandpa Heidt. William was again Mr Fearless - trying all kinds of
different moves on and off the sled. Amelia was, again, not so
impressed. It would seem we have one warm weather daredevil and one
cold winter daredevil!

While we were sledding at the hill, I spied something I've never seen
before. The family of four was using a secret ingredient to enhance
the speed of their sledding....