Super Squad Support Supermen Succinctly

Originating from the last surviving Kryptonian city of Kandor, an elite team of recruits assembled to form the diminutive Superman Emergency Squad. Kandor had been shrunken and kept in a bottle by the alien android named Brainiac. Upon defeating Brainiac and claiming the minature city, Superman kept it within his Fortress of Solitude of Earth-One, Each member of this Squad possessed superhuman abilities due to being descendants of Krypton. 

Led by Don-El aka the Super-Mite Superman, cousin of Kal-El aka Superman, they helped the Man of Steel whenever there was a need on Earth-One. While Van-Zee was also a member, he relinquished that responsibly for his career as a scientist. Secretly, he also assumed the alter ego of Nightwing. One other member, Vitor, had briefly left this life behind while attempting to court romance with Lois Lane and Lana Lang, although he soon thereafter rejoined he Squad. This group typically had a dozen active members at any one time. At times, they wore uniforms modeled after that worn by Superman, other times they wore distinctive scarlet colored uniforms. 

On Earth-Two, Kandor wasn't shrunken but instead was digitized by Zor-L, uncle of Kal-L aka Superman into a virtual reality replica. Zor-L housed this program within the Symbioship, which he designed to save his daughter Kara aka Power Girl when Krypton-Two exploded. As such, in place of a Squad supporting Superman that originated from his people, there was a Squadron... of which the golden age Superman was himself a member. 

This All-Star Squadron was formed at the beginning of World War II. Among its many members were Superman himself, as well as Crimson Avenger and the Wing, who mirrored the Kandorian known as Flamebird and his partner Nightwing. Another All-Star was the mighty mite Doll Man, secretly Darrel Dane, a physical look-a-like of Superman! Given this as well as his inherent superhuman strength and near invulnerability, attributes not attributable to his shrinking chemical concoction, there is a possibility he may have been one-eighth Kryptonian. 

Kal-El's great-grandfather Var-El teleported to Earth-One to attempt experiments that were illegal on Krypton-One. It is likely that his counterpart, Var-L, likewise did something similiar. If so, then instead of returning to Krypton-Two, he may have sired another family on Earth-Two while under the identity of 18th century lawman named Dane. This would explain Kal-L and Darrel's kinship, which they displayed when reuniting years after first meeting one another.

The actual doppelgängers of the remaining Kandorian members of the Superman Emergency Squad were Zator’s Seven who trained a young Osgood Armsby who later… along with Doll Man, Crimson Avenger and Wing, became a member of the All-Star Squadron and their third “Doctor” on staff. However, the Seven mostly operated behind the scenes.