>>89201796She becomes a secret agent despite becoming a teenager because of her amazing track record, but because she didn't receive the cure for the Adult Virus, she still ages normally. The rest of Sector V, even after Numbah 1 and 5 leaving, prove themselves to still be amazingly competent without their previous leaders, and they are also allowed to grow up without being decomissioned, which is why during Operation INTERVIEWS it becomes apparent that they were only pretending to have had their memories wiped when Father tries to find Numbah 1.
They stayed faithful to the KND even into old age.