Sam Wolowitz, Howard's father, was mentioned a few times though throughout The Big Bang Theory's 12-year run. The first mention dates back to season 3's "The Precious Fragmentation," which revealed Sam abandoned his family when Howard was 11, although his reason remains unknown.

There's very little known about Howard's father, Sam Holowitz, but that doesn't mean that he's not an integral part of his son's arc. He's been mentioned a handful of episodes throughout The Big Bang Theory 's 12-year run with the first one dating back all the way to season 3's "The Precious Fragmentation."