1910s
- 1918/19: Dale Ballard is born. In S7 E4, Connie says that Dale is 74 years old.
1920s
- 1923: Constance "Meemaw" Tucker is born.
- 1926: Charlie "Pop Pop" Tucker is born.
1970s
- 25-year-old Mary Tucker and 31-year-old George Cooper go to a bar, get drunk, and sleep together. Mary gets pregnant from that night.
- Mary and George have a shotgun wedding one month after discovering Mary's pregnancy.
- March 1975: George Cooper Jr. is born. This date is confirmed in S5 E18, in which Georgie confirms he will "turn 18 in March".
1980
- February 26, 1980: Sheldon and Missy Cooper are born. This date is explicitly stated in S2 E02 "A Rival Prodigy and Sir Isaac Neutron".
1985
- Pop Pop dies.
1989
- August: S1 E01 "Pilot": Sheldon and Georgie start 9th grade. Sheldon and Missy are explicitly stated to be 9 years old.
- November: S1 E06 "A Patch, a Modem, and a Zantac®": Sheldon's journal is dated November 9, 1989.
1990
- S2 E02 "A Rival Prodigy and Sir Isaac Neutron": Georgie says that he is in 10th grade. Missy says that she is in 4th grade.
- October: S2 E06 "Seven Deadly Sins and a Small Carl Sagan": Takes place on Halloween.
- November: S2 E09 "Family Dynamics and a Red Fiero": Takes place on Thanksgiving.
1991
- May/June: S4 E01 "Graduation": Sheldon graduates from high school, and Missy and Billy from 5th grade.
- August: S4 E06 "Freshman Orientation and the Inventor of the Zipper": Sheldon starts college, and Missy and Billy start 6th grade. Sheldon and Missy are explicitly stated to be 11 years old.
- November: S4 E15 "A Virus, Heartbreak and a World of Possibilities": Georgie, Jana, Missy, and Marcus go to see Beauty and the Beast, which was released theatrically in the US on November 13, 1991.
- S5 E03 "Potential Energy and Hooch on a Park Bench": Georgie drops out of school. George Sr. says that he "only has one year left", and in S5 E17, Georgie explicitly states that he dropped out his senior year (12th grade).
1992
- January: S5 E07 "An Introduction to Engineering and a Glob of Hair Gel": Sheldon starts the spring semester of his first year at East Texas Tech.
- March:
- S5 E11 "A Lock-In, a Weather Girl and a Disgusting Habit": Georgie says that he is 17 years old.
- S5 E12 "A Pink Cadillac and a Glorious Tribal Dance": A poster for the comic-con that Sheldon goes to says that it takes place March 6–8.
- April:
- S5 E17 "A Solo Peanut, a Social Butterfly and the Truth": The following episode picks up immediately after this one. Also, Mandy gets pregnant in this episode.
- S5 E18 "Babies, Lies and a Resplendent Cannoli":
- Plot revolves around the death of Isaac Asimov, which happened on April 6, 1992.
- Georgie says that he is 17 years old, and will "turn 18 in March". In S6 E03, Mandy says that their child will be born before Georgie turns 18, so it is likely that he is 17 years 1 month old at this time.
- The first few episodes of S6 take place in 1992, although the exact position of the events is uncertain:
- S6 E03 "Passion's Harvest and a Sheldocracy": Sheldon attends the first day of a new class at East Texas Tech. It is not stated whether this is the summer or fall semester.
- S6 E04 "Blonde Ambition and the Concept of Zero": Missy and Billy are still in 6th grade. It is possible that they are both in summer school, as they both have been shown to have bad grades in school, though this is not explicitly stated.
- S6 E05 "A Resident Advisor and the Word 'Sketchy'":
- Mandy now has a visible baby bump, and so she is likely in the second trimester of pregnancy.
- Sheldon says that he has an 8:00 am class. Since this class was never mentioned before, it is likely that this episode takes place at the start of the semester. Also, Oscar and Darren from S5 are no longer living in Sheldon's dormitory.
- August: S6 E06 "An Ugly Car, an Affair and Some Kickass Football":
- According to Sheldon's calculations, Mandy's fetus is "the size of a bell pepper". This means that Mandy is probably 15–20 weeks pregnant.
- Missy is attending school.
- George Sr. is coaching a high school football game; American high school football seasons typically start in August.
1993
- January: S6 E10 "Pancake Sunday and Textbook Flirting":
- Sheldon watches the premiere of Star Trek: Deep Space Nine, which aired on January 3, 1993.
- Mary says that "the outlet malls are still having their holiday sales".
- Mandy should have given birth by now, but this is likely a case of Longest Pregnancy Ever (which also occurred in the parent series).
- February/March: S6 E16 "A Stolen Truck and Going on the Lam": Missy says that she is 13 years old.
