June Squibb as Constance "MeeMaw" Tucker
MeeMaw, played by June Squibb, was Sheldon's grandmother from Texas. Sheldon was MeeMaw's favorite grandchild, whom she referred to as "Moonpie." Sheldon was deeply protective of her. In real life, June Squibb is an Academy Award-nominated actress, known for her role in Nebraska (2013).
Brian Posehn as Bert Kibbler
Professor Bertram Kibbler was a geologist at CalTech. At first, he was interested in Amy, but after a disastrous attempt at a first outing, the two went their separate ways. Brian Posehn has worked on a variety of programs, including New Girl and Mission Hill.