The Silver Age of Comics was known for Superman starting as "Superboy" in Smallville, and as years passed, this became increasingly ridiculous. It was written out of the mythos in the late 1980s ...

Krypto First Appears in DC Comics’ Silver Age as Superboy’s Dog Krypto first appeared ... version of mid-century America, only with flying cars and high technology. But the average family ...

For the rest of the Silver Age, Krypto became a fixture of Superboy stories ... DC decided that a little dog flying around in a cape was too childish for their audience, and they wrote Krypto ...