Missy Preston-Logan is Bill & later Ted's former stepmother. She later marries again to Ted's brother Deacon.
She was a senior in high school when Bill and Ted were freshmen, meaning she is most likely 3 or 4 years older than the two. She marries Bill's father, Ted's father, and Ted's little brother Deacon throughout the Bill and Ted franchise.
She is generally very friendly and supportive of Bill and Ted, and mostly unaware of the awkwardness her presence in their lives and various marriages causes for them.
She is shown to have an interest in the occult.
- Ted asked her to Prom in 9th grade.