Foster's Home for Imaginary Friends, Season 1

[Frankie watches Mac, Bloo, Wilt, Eduardo and Coco play together in the yard while Mr. Herriman deals with paperwork]

Frankie:
I think this one is different. I don't think he's gonna abandon his friend!

Mr. Herriman:
Don't be so naive, Miss Francis. It's unbecoming. You know as well as I that it is just a matter of time before young Master Mac tires of his beloved Bloo, at which time his visits will cease, and Master Bloo will be placed in the care of a new child... who will eventually tire of him, as well.

Frankie:
Ugh, why do you always have to be so negative? I mean, come on! Look at that. They're absolutely inseparable! Plus, the guys have really taken to him, too.

Mr. Herriman:
It's just a cruel fact of life, Miss Francis. Every child tires of their imaginary friend eventually...

Frankie:
[leans over his shoulder and gives him a knowing grin] Yours didn't.

[She leaves, passing a portrait of Madame Foster. Herriman stops briefly, but continues working, knowing Frankie's words are true]