The "kids" were a trio of robots built by Commander Jett Reno to assist her after the USS Hiawatha crashed on an interstellar asteroid in 2256. Constructed from scavenged Starfleet components, they were equipped with multi-vector propulsion and inertia dampeners, and could hold a large amount of weight. The three of them could function separately or combined into a single unit.
In 2257, Reno sent the kids to investigate an away team from the USS Discovery. Viewing Christopher Pike, Michael Burnham, and Nhan through the kids' live video feed, she used them to speak with and guide the team to her location. (DIS: "Brother")