Justice League of America, Vol. 1

As the heroes of the Justice Society prepare to face down the villains attacking Earth-One, Sargon the Sorceror joins them. In the Thunderbolt dimension, the Earth-One Johnny Thunder has the Thunderbolt explain how Black Canary's double lays in a glass coffin with her late husband. When Canary and her husband had their child, Dinah, the Wizard cast a spell upon the baby causing her cries to be amplified. To help them, Johnny Thunder of Earth-Two had the Thunderbolt hide the child in the Thunderbolt dimension and caused all concerned to forget about Dinah. The Earth-Two Thunder, held prisoner by his counterpart, manages to escape and knocks out the Earth-One villain. The Thunderbolt is then loosed upon Earth-One and helps the heroes take down the villains. When Superman later arrives, he explains that when Black Canary had first joined the JLA from Earth-Two, he had stopped off in the Thunderbolt dimension and, with the elder Canary's agreement and Thunderbolt's help, had swapped her for her now fully grown child, Dinah, and altered her memories.