There were slight differences between Earth-154 and Earth-216:
- The names of Batman and Superman's wives were known on Earth-154: Kathy Kane and Lois Lane.
- Superman had graying temples on Earth-154 by the time his son reached his teens, he didn't seem to have aged on Earth-216.
- Flying cars were common on Earth-154 by the time Batman and Superman's sons reached their teens while technology was much the same as the real world 1970s on Earth-216.
- Batman was such a popular hero on Earth-154 that teenagers wear Batman costumes that Bruce thinks nothing about his son going out in costume sans mask. There is nothing shown on Earth-216 even remotely resembling this.
The events of Earth-216 were duplicated in a computer simulation where Superman and Batman did not create a mother figure for their offspring.
In the premiere issue of the fanzine Omniverse (1977), Mark Gruenwald argued the existence of an "Earth-E", filled with the Super-Sons and that the majority of stories between All-Star Comics #57 (March, 1951) and Brave and the Bold #28 (March, 1960) covered the adventures of their fathers rather than the Superman and Batman of Earth-Two or Earth-One. 
He also provided a synopsis for the Superman and Batman of that reality:
- Kal-El landed on Earth as a 2-year old in 1930, had a Superboy career in Smallville, worked as a reporter for the Daily Planet, and married Lois in 1960.
- Luthor is older and bald.
- There is no evidence of Superman's cousin being on Earth.
- Bruce Wayne's parents were murdered in the 1930s, he began his Batman career in 1950, and married Kathy Kane by 1960.
- Bruce Wayne had a playboy brother named Thomas who was deceased.
- Bruce Wayne's partner was college professor Dick Greyson.
- Batman's friends/allies included Vicki Vale, Batgirl, Bat Hound, and Bat Mite.
- Neither Superman nor Batman had a group affiliation.
- Crisis on Infinite Earths: The Compendium identifies Earth-154 as the original universe featured in World's Finest #154 and Earth-216 as the "Super-Sons Earth" which first appeared in World's Finest #215. However, for indexing purposes, the DC Database has chosen to use Earth-154 as the main universe designation for the stories featuring Batman, Superman and their offspring. It is considered that this "merger" doesn't affect continuity since there are no indicators that both Earths contradict their respective timelines.
- A duplicate recreation of the Earth-154 Super-Sons' Universe was created during the Infinite Crisis. This recreation and all of its inhabitants were destroyed at the end of the Infinite Crisis.
- There was another reality (Earth-391) where Superman and Batman had sons but events clearly show it was not related to either Earth-154 or Earth-216.
- No trivia.
- Characters from Earth-154
- Other things related to Earth-154
- Earth-154's Comic Appearances
- Reality Gallery: Earth-154
Links and References