After a year at the Barn Theatre, Barber moved to Chicago and spent five years working his way up in
The Second City improvisational comedy troupe. He also appeared in episodes of
How I Met Your Mother,
Gilmore Girls,
Californication,
Monk,
The Mentalist, and ''
Grey's Anatomy''. Barber played
Jimmy Speckerman, who bullied
Leonard Hofstadter at high school, in
one episode of
The Big Bang Theory. He was cast as George Cooper Sr., father of
Sheldon Cooper, in the spin-off
Young Sheldon that premiered in 2017, and mentioned in an interview that some fans were confused by his different roles in the two related series. Barber also played Cooper in "
The VCR Illumination", a 2018 episode of the parent show's
twelfth season; the character is deceased in the series but appears on an old
VHS tape that Sheldon plays. ==Personal life==