Catcher blocking plate

Question
Tom,

My daughter's team (10U) played a team recently with a rather large catcher (NSA). This girl looked like she was 12 or older, but that's beside the point. She was a really good catcher. I'm wondering about something though. This girl made it impossible to steal home. If there was a runner on 3rd and she missed the pitch, she would get the ball and then run and slide down into the plate on both knees and basically straddle the plate with legs so that no part of it was showing. We had two girls try to steal home on a missed pitched and she would come sliding in to the plate on her knees. She was so big that our girls had no chance of getting to the plate. I've not seen anyone do this before; however, this was only the 3rd tournament that we played in. I didn't realize that they could totally block off the plate like that. She was basically sitting on it on her knees. I guess it must be okay though because there we no calls made. One of our girls that tried to slide collided with her hard when they both got to the plate, and she was rulled out. What are your thoughts on this?

Answer
Sounds like good softball to me.  As long as the catcher has the ball she doesn't have to allow access to the plate.  If she doesn't have the ball she can't prevent the runner from touching the plate.

I'm kind of surprise that a catcher can make the play on the runner comming from third unassisted on a passed ball.  What am I missing here that would enable the catcher to make this play.  I don't do anything with NSA.

Tom