The beginning of the end of innocence?

Miles and Eliza had a roaring good joke going between them at dinner last night.

Miles: (in that na-na-nany booboo sing-song tune cherished by children all over the world) Eliza is a caca. (laughter)

Eliza: Miles is a caca. (laughter)

Miles: Eliza is a caca. (laughter)

Eliza: Miles is a caca. (and so ad infinitum)

Me: Children, we do not talk about caca at the table.

Miles: (in an almost teenager-like sarcastic tone with an indulgent little chuckle): Sure, Mom. We NEVER talk about caca at the table.

...it was only a matter of time given his Brigham blood. Of course, mother that I am, it was all I could do to stifle my appreciative giggle.