Mike Heck (the father) is heartbroken and angry when he overhears one of Sue's friends, Shannon, mocking her and intentionally not inviting Sue to a sleepover [2].
The episode "Sleepover" (S2E8a) features a magical truth-telling game that threatens to reveal Star's crush on Marco [11].
"The Haunting" [7, 9] Original Air Date: November 20, 2006 [7] 📝 Synopsis
If neither of the above is the show you are looking for, "Sleepover" is a common episode title in other series:
"Errand Boy" [1] Original Air Date: November 17, 2010 [1]