Michelle Obama (guest voice Angela Bassett) makes an appearance on The Simpsons when she comes to visit Lisa.
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Nikki (guest voice Sarah Silverman) kisses Bart despite the fact her parents are suing the school for Bart kissing her.
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The Simpsons Season 21 Episode 15 Quotes

I cheated wrong. I copied the Lisa name and used the Ralph answers.

Ralph

Bart: Where's Mrs. K?
Principal Skinner: Mrs. Krabappel had to go to Portland. Apparently the people she hired to deprogram her sister from that cult were an even worse cult.