Fuckin' gnosticism man, not even once. No wonder early Christians wanted to stomp that shit out as quick as possible.
IMO this is not indefensible in and of itself. Depends on the likelihood of the condition affecting future children, how long the disabled kid is expected to live, whether enough respite care is provided that the other kids can at least spend some time doing normal stuff with their families and whether they purposely make the gimp the center of everything.
Even then it can be a total crapshoot. Often times if tended to appropriately kids with minor disabilities can have some semblance of a normal life aside from extra physio and doctors' appointments with an IEP. Knew a girl who literally had almost half her brain removed short after birth due to a gargantuan tumor. Don't want to go into too much detail about her specific health situation but it ended up being really good and the brain grew to compensate for most functions, she adjusted to her limitations enough that she needs very little if any help for activities of daily living. Her parents were told there was a good chance she could end up criptato level but did their best to prevent that from happening, got lucky, and did decide to have another kid once they realized she was doing well and were assured it was not genetic.
The best part was that her family was a bunch of closet Aryan Nation white supremacists at home and she didn't have a great verbal filter, so she'd swear a lot and tell the most offensive jokes about "niggas", "spics" and "wahoos" all the time but had just enough tard teflon to get away with it, it was hilarious. Whatever else you can say about them her family handled this properly IMO and she is restricted on her internet activity nowadays to prevent her from inadvertently ending up a lolcow.
People who have a disabled kid, take advantage of the best genetic counseling and prenatal testing in the world, then keep getting knocked up and taking every pregnancy to term despite bad odds are the shitstains I have a problem with, Hartley being the most infamous. Those poor harlequin ichthyosis are the ones that kill me the worst and if you let that shit go to term on purpose that shit's like a war crime.