This is absolute bollocks!!
"if the new child has any disabilities then that’s it for the rest of your kids in terms of education and future lives.+"
I hope to god you've never expressed this to any friends who's kids have a disability? That their other kids lives are fucked before they even start?
Firstly disability is a catch all, there isn't one fucking rule for all the" normal" children and then one for the rest of them, going around with their disability ruining the lives of the siblings.
Secondly I think I'm too fucking angry to be coherent.
Not every disabled person requires a sibling to care for them after their parents death. Lots of disabled adults live independent, full lives, marry l, have kids and work. How is that taking away their siblings futures?
Even if they do need care, there's no reason it has to be a sibling or that if it is it requires the sibling to sacrifice their entire life
Many of us won't be able to pay for our kids Uni etc regardless whether one or more of them are disabled, or will be able to do so regardless of whether one or more of them are disabled and that includes paying for the disabled child to go to Uni.
Even if we presume "any disability" you meant the severe end, I know families who's kids have conditions like (mosaic) T18, Cerebral Palsy, etc who do all the things they would have done as a family albeit with tweaks.
And that's before we even get onto the value siblings bring to each others life regardless of their abilities, and the value disabled people add to society.
Aagghh!!!!