It’s the fact that the source of sound is often 10-20 cm from your ear. As the average source-ear distance grows though, their lung volume grows too so you end up with a looong period of dangerous sound pressure levels.

Babies can scream at 120db. (supposedly 130, but I find that hard to believe)

not only that its at about 3.5khz. now look at this graph: https://en.wikipedia.org/wiki/Equal-loudness_contour

Right in the loudness contour.

children, less so, babies yes.

number two is nowhere near as loud or as prone to screaming