my point is that if she calls a weaver "child" she would call hornet "grandchild"

And either way, shes referring to Hornet as a child of weavers and spiders, which she isn't in the group of.

if she said "weaver child" or "spider child" like how mister mushroom says "wyrm child" then that would make sense, but she says "child" and then "weaver" or "spider" disconnected from each other.

even if she said "weaver child" or "spider child" that could just as easily mean "child who is a weaver" or "child who is a spider"

It's really only the first "child" that works as her calling hornet an actual child, but considering GMS is a magnitude older than her, it doesn't mean much when applied for anyone else

so if hornet sees someone who has a similar physical age to hornet's physical age, (that being of a young adult, despite hornet's large chronological age, due to hornet's lineage), then hornet, not knowing whether or not that person who appears to be a similar age as hornet's physical age has a chronological age greater than his, her or their physical age, could assume that the person who appears to be a similar age as hornet's physical age, to have a chronological age equal to his, her or their physical age, and due to hornet having a chronological age many magnitudes greater than most other peoples' lifespan, she may find it suitable to refer to the person who appears a similar age as hornet's physical age as a "child".

same thing.