Onions in our grass

Brenden: Mom, look, we have onions in our grass.  Grandpa had these, but he didn't take them in the house and cook them, he threw them in the trash.

Mom: Onions?

Brenden: Yeah, come look!

Mom: Do you mean mushrooms?

Brenden: Yeah, what did I say?

Mom: Onions.

Brenden: They aren't onions, they are mushrooms.  You thought they were onions?

Mom: No, you thought they were onions.

Brenden: Mom, they're not onions, they're mushrooms!  You're silly.