Of all the covers Superman has made to protect his Kryptonian heritage, his original idea for Supergirl is by far his worst. When Clark's cousin Kara came into his life, the Man of Steel came up with the most unbelievable plan to integrate her into society.
Despite how prominent the Super Family is now, there was a time when Clark Kent was the only Kryptonian around. Aside from files left behind from his father, Jor-El, he had no one to teach him the culture of his home world or talk about its past. That changed forever when Superman met Supergirl, a fellow survivor of Krypton and his cousin on his father's side. For once, Superman wasn't alone in the world and had someone who shared in the despair of a dead world, as well as the responsibility of their great powers. Unfortunately, even DC admits Superman essentially ruined Supergirl's origin story.
Which makes Clark's original treatment of Kara that much more weird. Superman’s history changed forever when Supergirl first appeared in Action Comics #252 in the story “The Supergirl from Krypton!” by Otto Binder and Al Plastino. After a rocket crash lands on Earth, Superman discovers Supergirl within. He listens to her story and realizes the young girl is actually Superman’s cousin from Krypton. Because she actually lived to see Krypton, it could be argued that Supergirl is Krypton's real legacy more than Superman. Clark is happy to finally have family that shares his Kryptonian history and Kara is equally overjoyed she won't have to face this new world alone. But when Supergirl inquires if she'll come to live with Superman, he tells her that her sudden appearance may arouse suspicion in his life as Clark Kent. Instead, he takes her to the Midvale Orphanage where he helps her come up with her secret identity as Linda Lee so she has somewhere safe to live and acclimate to Earth's culture.
Needless to say, the story is a bit unusual considering how much Superman cares about his cousin, Supergirl. In Clark's defense, at the time it might have looked a bit odd for a bachelor to suddenly be living with a teenage girl, even if she was family. But Clark's almost lightning decision to send Kara to live at an orphanage is not only short-sighted, but it's also incredibly unlike the family-oriented hero fans know and love today.
Clark Kent loves his family. His Ma and Pa, his wife, and his son. He’s dedicated to them all and makes sure to do right by them. This is why it's so odd that when presented with a flesh and blood relative, Superman sends his family away. Not to live in Kansas with the Kents, or even a trusted friend like Lana Lang, but to an orphanage surrounded by strangers. Aside from the callousness of the idea, it's incredibly dangerous. Kara had no clue of Earth customs or even full control of her powers. She could have tussled with a powerful enemy she wasn't prepared for or accidentally hurt an innocent. Thankfully this story was retconned because Superman's original treatment of Supergirl is by far his worst look.