Who is sorry now?

Yesterday, Eliza said "Nooooo" to Sadie in a very demanding voice. Sadie cried.
I said, "Eliza, 'say sorry Sadie'."
Well, apparently Sadie heard, "Say sorry, Sadie." (Punctuation really change the meaning of a sentence sometimes).
So Sadie repeatedly says, "Sorry, Eliza. Sorry, Eliza."
Eliza says nothing for several seconds. Then she looks at me and very sincerely asks, "Mommy, why is Sadie saying sorry to me?"

I had a teaching moment here but I blew it because I just started laughing hysterically and then both of the girls joined in the laughter too.