This is what is known of the children's futures, c. 2023 AD, as detailed in Future Shocks
His father only studied the occult...Eric lives it as a trained sorcerer in the Hermetic arts. He uses his knowledge as a member of the Ghostbusters
Her exact relationship with the Ghostbusters is undefined, but she apparently works with them in some capacity--she's credited with "checking out" the Eiffel Tower
Dr. Johnathan Christopher Spengler
Heir to the Spengler family legacy and leader of the future Ghostbusters, John is a brilliant but sometimes mischievous scientist always tinkering with Ghostbuster technology, looking to improve it. He and fellow Ghostbuster TJ Anderson are slowly falling for each other.
Dr. Eden Spengler
Unsurprisingly, Eden will grow up to become a brilliant scientist in her own right, specializing in exploring the same sort of metaphysical theories her father pioneered (though she also is a wiz with computer technology). A member of the Ghostbusters, she doesn't usually go on busts, but is there when needed.