The bell door

So I was playing with Erin at home earlier and it was already getting dark.

Me: Erin, can you close the door for me?

Erin: mmmm, which door? the beel door?

Me: huh, what bell door?
(Erin went to the door, slammed the screen door causing it to rattle - the sound of metal bouncing to another metal.)

Erin: See? It's like rinnnggg-rinnnggg.

 That there you go, the bell door.