'Modern Family' Celebrates 100 Episodes With an Awkward Reunion (Video)

Modern Family rings in its 100th episode on Wednesday, Oct. 9, and the ABC comedy is celebrating with a visit from a previously unseen extended family member.

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Cam's (Eric Stonestreet) sister Pam (guest star Dana Powell) arrives at the Tucker-Pritchett household in "Farm Strong" -- and though it's their intention to announce their upcoming nuptials, the two seem to chicken out when Pam arrives in a rather sour mood.

"The damn airline lost my trunk," she says, channeling her best Debbie Downer. "Now I'm going to have to make new clothes."

Watch the exclusive clip above ahead of the 100th episode, which premieres at 9 p.m. on ABC.