The couple first captured hearts around the world in 2018, when they fostered an egg at Sea Life centre in Sydney.
While the other penguin couples proved not to be great parents, leaving their eggs to get cold when going off for a swim or to play, aquarium staff noticed Sphen and Magic making their own nest collecting ice pebbles.
The pair were given a dummy egg and, when they showed strong nurturing skills, they were entrusted with a real egg from another couple.
Once the egg hatched, the aquarium said the couple took turns caring for their chick, and were "co-parenting exceptionally well".
Following their success raising their first baby, Lara, the penguins were given another chick to take care of, which hatched in November 2020.
The aquarium has issued a call-out for name suggestions for the new baby from around the world, and will choose the best one for the "waddling chick".
The person who picks the chosen name will meet the penguin family or, if they're from overseas, will get the chance to have a Zoom call with them.
The keepers first started to noticed Sphen and Magic's fondness for each other when they began bringing each other carefully selected pebbles for a nest.
Had either not been interested, they would have rejected the pebbles by pushing them away with their beak. Instead, each admired the pebbles they were given.
“You would see Magic standing in his spot looking for Sphen, and he would call and Sphen would come running over and give Magic a little bow and sing as well,” Tish Hannan, head of penguin supervision at the aquarium, said at the time. “They’ve chosen each other. That’s it. They’re bonded now.”
The other penguins in the couple's colony were still sizing each other up and deciding on a partner at the time.
“They were recognising multiple different bird calls and bowing to different individuals,” Hannan said. “We saw none of that behavior from either Sphen or Magic. They weren’t interested in other birds in the colony.”
Those wishing to submit a name have until 1.59pm on Sunday 24 January.