If they go on vocabulary at age 3, my DS2 should not be achieving anything. At 3yo, he was non verbal.
By 9yo and Y4, he is currently working on lvl 3 Maths, lvl 2 reading, lvl 1 writing. He can talk and hold a conversation, and uses words like 'regurgitate' in everyday conversation, with correct meaning etc.
His development was not delayed because of any lack of parenting, but through disabilities that were NOT all dxd before he started YR. Some were, not all.
If it was parenting problems causing my 1st DC (who got 4 years of my undivided attention) and my 3rd DC (who obviously didn't, granted, but still got 2 hrs a day where it was solid interaction 1-2-1, through Physio, OT, proprioception and SALT excercises) - then how do you explain the fact that my second DC, in between the two, was on the G&T register at 2.5yo at preschool, and is currently at age 10yo working at around 3-5 years ahead of their peer group in all areas?
But with my first DC, even the class teachers and SenCo blamed her issues on my 'poor parenting' due to my age, until they had personal dealings with my second DC, who was 4 years younger.
So yes, these issues CAN be blamed (unfairly) on 'poor parenting'. And a good parent trying to get help for their DC's delays can be labelled as a 'nuisance parent' because they are trying to get the early intervention (that costs money) that their DC needs.
With my youngest DC, who has just been dxd with hyperactivity, it has been plain to see from a very young age (months rather than years) that he has different issues to my other DC's. I first spike to the HV about it when he was 5mo. It was only when he was 20mo that he saw the Paed and got a dx. He has already been referred to the EP and SALT. Why so much quicker than with my first DC? I suspect because I am not 16yo any more (I am much a bit older, at 31), I have 'shown' that it isn't my parenting, because DS1 disproves that.
He has also got severe food allergies. These were first noted when I had to eliminate them from my diet while BF when he was just 8wo. It has taken until today, when he is 21mo, for him to see the allergist and get a full dx of severe CMP allergy, severe nut allergy and moderate soy allergy through skin prick testing.
That is 19 months of fighting the NHS for a basic test that takes 15 minutes, and on the basis of which I have now been provided with life saving equipment for him (Jext pens).
If these appointments were not so bloody hard to come by, I could have started interventions much sooner.