This Actor Joins 'Big Bang Theory' Cast as Sheldon's Brother Producers announced on Wednesday that Jerry O'Connell will portray Georgie, Sheldon's older brother. Georgie is also a central player in CBS's Young Sheldon – the 'Big Bang' prequel. Emmy winner Laurie Metcalf Both of the new additions are expected to appear in a May episode for Sheldon and Amy's wedding.