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Why She Left: Reports surfaced in April 2013 that Morris was expecting her first child with boyfriend Taylor Hubbell and a source told us at the time that it was "unlikely" she would return as a regular in season five. (They were right!)
How She Exited: After apparently becoming super-smart overnight, Brittany left McKinley mid-way through her senior year after being offered early admission at MIT. It is unknown if Lord and Lady Tubbington accompanied Brittany to MIT, or stayed at home.
How She Returned: Brittany S. Pierce graced the halls of McKinley again for Glee's special two-part 100th episode extravaganza and revealed that her fellow MIT collegues only view her as a "math monkey." She ran off with Santana for a romantic vacay, but when Santana returned to NYC, Brittany was no longer be her side and there was no mention of Miss Pierce's blatant absence.