The bug

If a baby cow tries to climb stairs while there's a 1 block tall space next to it, the cow will suffocate.

Steps to Reproduce:

1. Create a box that allows the cow to climb stairs while also next to a 1 block tall area, as shown below.
2. Spawn a baby cow.
3. Use wheat to make the baby cow follow you. (Stand/fly on the side of the box with the staircase.)
4. If done correctly, the cow should start taking damage, as shown below.