Warning: contains spoilers for Superman Red and Blue #5!
While Superman is the Last Son of Krypton, his adventures have gradually uncovered more survivors from his home planet, and Krypto the Superdog is one of the most beloved. Similarly empowered by Earth's yellow sun, Krypto has long been an ally to Superman and his family, helping to redeem Superboy-Prime and currently fighting for life after being poisoned in Supergirl: Woman of Tomorrow. But while the official story is that Krypto was Superman's childhood pet, Judd Winick, Ibrahim Moustafa, and Wes Abbott's 'Fetch' - from Superman Red and Blue #5 - reveals the Superdog's origins are darker than they seem.
Krypto first appeared in 1938's Adventure Comics #210, when Clark Kent hears of a mysterious superstrong dog at large in the city, chasing it only to discover it can also fly. The young hero soon discovers Krypto's rocket, launched before his own but subsequently knocked off course and arriving on Earth later, complete with a note from his father Jor-El explaining how the family's beloved pet had to be used in one of Krypton's final experimental rockets, paving the way for Kal-El's own escape. Co-created with Curt Swan, Superdog was one of many elements added to the Superman mythos by Otto Binder, enhancing Superman's connection to this home planet and fleshing out the events leading up to its destruction.
In 'Fetch,' Krypto's origin is given a new spin, with a young Clark immediately sensing the arrival of a familiar craft. Rather than having grown over the journey, Krypto emerges as a puppy, giving Clark a childhood companion who can match his speed and flight while making him feel less alone. But while Clark runs off to play with his new four-legged friend, a hologram of Jor-El - his biological father - is projected from the craft, revealing that rather than being a family pet, Krypto was always a lab animal intended for testing, but one that escaped Jor-El and subsequently bonded with his son.
This change to Krypto's origin doesn't actually clash with the original version of how he came to Earth, which can be read as simply taking place slightly later in time, but it does cast Jor-El in a more unfavorable light, depicting him as a colder, more clinical presence. It's an alteration that jibes with recent depictions of Jor-El, who - in the pages of Superman - emerged in the modern day only to reveal himself as a complex, untrustworthy figure whose recklessness cost Clark and Lois several years of their son Jon's life thanks to some unexpected time travel.
Tragically, Jor-El was sent back to die on Krypton without his son being able to say goodbye, adding new layers of complexity to how Superman regards his past. Superman Red and Blue pulls a similar trick, painting Jor-El in a harsher light, and underlining the tragic whims of fate that have dictated Superman's life, gifting him a vital companion he was never actually supposed to meet or care for. Krypto remains a beloved part of Superman lore, and like any comic-book hero, stays vital through frequent re-imaginings, even those that turn a beloved family pet into a lab animal who just so happened to survive.