It is indicated that Hank and Dean would be 19 years old, if they were not constantly being killed and replaced with clones (they believe themselves to be 16, however).
The running joke about Catherine the Great is a reference to an urban myth that Catherine died while trying to engage in sexual intercourse with a horse. The horse was supposedly suspended by a harness that snapped, dropping the horse onto her and crushing her. In reality, she died from a stroke.
WILHELM SCREAM: First act, right after the first "anti-personnel" device explodes and just before The Monarch walks in.
Myra's car is a 1968 Ford Mustang GT with the Highland Green paint job, made famous by Steve McQueen in Bullitt. The car sold at auction in January 2020 for $3.74 Million.
The episode's title is a reference to Maya Angelou's first of three autobiographies titled "I Know Why The Caged Bird Sings"