In Adventure Comics #240 (July 1957), another super-coincidence when Superboy encounters a Kryptonian robot in the sky above Smallville. The robot explains that it was built as a teacher for Kal-El years before Krypton’s demise and that Superboy must pass 3 tests to prove he can use his powers and continue to be Superboy.
Known surviving Kryptonians: 6 (this number now includes a dog as well as a robot!)