Stairway to Heaven?

This week I went all the way up the stairs all by myself!  It was a lot of work, but it was so worth it.  I saw mommy go up to get the bath ready for me, and I just followed her up.  I was on a mission, so I did it.  Luckily daddy was there to follow me, because it is a little tricky.  I heard Mommy and Daddy talking about needing to put up a gate now, but I'm not sure what that is all about - a gate for what?