The Cubs have a new third-base coach, per Buster Olney of ESPN:
Willie Harris, longtime utilityman, is expected to be the Cubs' third base coach.
— Buster Olney (@Buster_ESPN) December 8, 2020
Confirmed here (though not yet announced by the team):
Willie Harris will be the Cubs' new 3B coach, source confirms. Nothing official from the team yet. The job opened up when Will Venable left to be the new Red Sox bench coach. @Buster_ESPN first to report.