|The Venture Bros. character|
Escape to the House of Mummies Part II (mentioned)
Colonel Lloyd Venture (father)|
Jonas Venture Sr. (son)
Dr. Thaddeus Venture (grandson)
Jonas Venture Jr. (grandson)
The Monarch ("blood relative")
Hank Venture (great-grandson)
Dean Venture (great-grandson)
Dermott Fictel (great-grandson)
Jonas' father is a character who has been referenced, but never seen, on the series The Venture Bros. His last name is presumably Venture, though his first name has not been given.
Colonel Lloyd Venture was an adventurer, super-scientist, and milliner who belonged to the original Guild, a Gilded Age predecessor to the current Guild of Calamitous Intent. He had a son, name currently unknown, who was also a super-scientist.
- Escape to the House of Mummies Part II (mentioned)
- Pinstripes & Poltergeists (mentioned)
- In Escape to the House of Mummies Part II, Dr. Thaddeus "Rusty" Venture states that his father's father was a super-scientist.
- In the episode Pinstripes & Poltergeists, Thaddeus Venture is hit with a notice of a zoning violation for the Venture Compound for not using enough of it for prosocial, altruistic purposes. According to the notice, his grandfather had long ago zoned the Compound for the "care and upkeep of American rightness and the active defense of her civil needs." Had the matter not been taken care of, Thaddeus Venture would have lost it to the Mammoth Corporation. The lawsuit was part of a scheme launched by Monstroso.
- Jackson Publick confirms on the creator commentary for The Venture Bros. & The Curse of the Haunted Problem that Jonas Venture Sr.'s father has not been named on the show, only Jonas' grandfather Lloyd.
- In The Saphrax Protocol it is revealed that The Monarch is a blood relative of Dr. Thaddeus Venture. Earlier in Season 7, a scene in Arrears in Science implied that Jonas Venture Sr. impregnated Mrs. Fitzcarraldo, making him The Monarch's real father. If that is the case, The Monarch would be the grandson of Jonas' unnamed father.