Michelle Williams On 'Cougar Town' Season 4 Premiere, Shimmying And Using An Accent (VIDEO)

After years of talk, Williams appeared opposite Busy Philipps, her real-life best friend and godmother to her daughter, at the end of the Season 4 premiere on TBS. The scene (above), which aired as the credits rolled, was billed as what's to come on "Cougar Town" ... "or not. [They] haven't decided." According to the voiceover, Williams could join the cast as Laurie Keller's (Philipps) cupcake-loving Southern foster sister.

Philipps told show producers that Williams would guest star in Season 1 of "Cougar Town," but nothing ever came of it. "And then she was nominated for her third Academy Award and they're like, 'Hey, maybe one of your friends would wanna ... ?'" Philipps told E! Online. "I said, 'I told you Season 1 that she would do it! You lost her now to the third Academy Award nomination.'"

In April, Philipps said she wanted Williams to play her "bookish sister who hates me."

"Cougar Town" airs Tuesdays at 10 p.m. EST on TBS.

Midseason 2012-2013