A researcher decides, out of curiosity, to see if it's just human adults that are dangerous, and how far back that 'dangerous' could be listed. Then they read the study of a human toddler named Pib, and research other human toddlers aboard other ships that employ adult humans. Let's just say the kill counts for the toddlers, and the description of what these kids did, caused the researcher to end up in therapy, terrified of human children.
Researcher Ornsen should have known that undertaking veracity research into the whole "Humans Are Space Orcs" thing was just asking for trouble. Ze started with noble intentions, which we all know is the final impetus on the slippery dip to Hades.
Case file: Human Pib. The first known toddler with a kill count. There were others that sprang up, but Pib was the first. Therefore, they were also the most notorious. The worrying part was that there was no de-escalation of incidents in Pib's record. In fact, the incidents seemed to be increasingly more precise.
Research into Human young was disturbing. Even at their most helpless, they could randomly emit any number of toxic substances. Debate continued to rage as to whether this was a survival mechanism or not. However, the key point appeared to be when the Human larvae reached the stage where they could move themselves about and manipulate their environment. That was when things became -at least scientifically- interesting.