I refer to my own thread titled "failed 8 month development check"
here. Very old thread but at least it proves I am not a Troll (dating back to 2002!!).
Not a horror story, but my DD was finally diagnosed with a genetic condition that basically causes overgrowth and delayed development. The condition is mainly to do with overgrowth but the global delayed development is due to this also.
Took us nearly 2 years (she was by then nearly 3) before we received a diagnosis but in the meantime she received portage (immense help and she came on so much in such a short space of time), also saw occupational therapist, physiotherapist, was under the eye hospital, hearing, etc.
She has reached all of her milestones (albeit a bit later) and goes to mainstream school (with a little bit of help).
She does everything that any 7 year old can do, albeit sometimes it takes her a bit longer to master the skill.
She receives SALT during school hours (twice a month, I think) and also still attends the outpatients for hearing (had grommets three times, always fell out, hearing at the moment seems to be fine, although a bit of glue ear). No longer sees physiotherapist, ocupational therapist, etc.