Creation
At the end of the Hotel Oblivion arc of Umbrella Academy comics, the Sparrow Academy was introduced, and among the team was an odd cube shaped box which was apparently apart of the rival team, who are all said to have been born on the same day as the Umbrella Academy.
Due to delays on Umbrella Academy volume four, we’ve yet to see the Sparrow Academy in the comics outside of their cameo.
Other Media
Umbrella Academy (Netflix Series)
The cube member of the Sparrow Academy would be first named in the Netflix show. Christopher despite his appearance is a party animal. While he doesn’t verbally speak, his mumbles can be understood by his siblings. Christopher supposedly died when he exploded after encasing a dimensional rift.