By forgotten, I mean sitcoms that nobody else you talk to seems to really remember.

How to Marry a Millionaire.

This used to air in reruns on either a cable channel or a local affiliate in the 1980s. Haven't seen it on cable/broadcast in decades, and no one I've spoken to in person even remembers it, although a few people here recall it.

Two Of A Kind (Mary-Kate and Ashley's Full House follow up)
So Little Time (their final show)

God bless you and them always!!!

Holly (a day one fan of the girls)

Empty Nest

The Mommies

Back to You, with Patricia Heaton and Kelsey Grammer from around 2007