This photo is taken from the episode "You Gotta Get a Gimmick." During that installment, Gabrielle looks more into her heritage.
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Desperate Housewives Season 6 Episode 12 Quotes

We really wanna join you and help with that diversity thing.

Gabrielle

Gabrielle: I know I'm biased, but I think she's a budding genius.
Juanita: I'm Mexican?