As the parent of two, with one extremely challenging kid and another that was assumed to be not challenging...
I suspect there were signs for years that things were wrong. They are very subtle. I missed them too. Almost lost our easier kid.
You see, the challenging kid absorbs SO much time and attention and energy that the other kid does NOT get what they need. They seem to be doing well, so we assume they don't need more attention. Unfortunately, they actually need way more than we think. And in not getting it, they ARE damaged. We managed to catch mine mid-teens, and turned the situation around. But we underestimate just how hard it is to be the sibling of a high-needs child.
Like most families, even with your daughter's extreme call for help, you all fell between the cracks. Nobody takes the whole picture into consideration. And mental health issues are poorly supported at the best of times.
Wish I had better answers for you.
