All Rainbow Blaze ever wanted was a son to carry on his family tradition, but when he ended up with a filly instead of a colt, he tried to deny it, but with all the events that he and Rainbow Dash went through in her life, he became divided on maintaining his family tradition and accepting Rainbow Dash as the daughter he had.

It was a typical evening for Source Code, a proud Las Pegasus resident. He was going out for a walk when he gained a companion, in the form of a young pegasus named Spectrum Winds.
Spectrum decides to stay with Source Code for a while, even though Source knows Spectrum's family must be worried about him.
It's when Source realizes just how much Spectrum's company means to him that things complicate for the two of them.