Well, they were identical twins, and it's genetic (not hereditary), so if one had it, the other one had to have it.<quoted text>
Both twins born with the same severe disability? Wow. My problems get less significant every day.
The kicker that made me cry (years ago when I met this friend and her family and the nephews): The parents wanted more kids, but knew the two boys would take so much time, money, and energy, they felt that they should just focus on those and do everything possible to give them a great 20 years. They did this knowing that they'd be childless the rest of their lives.
To me, that's a damn big sacrifice. You love kids and want to have them, and part of that is, enjoying watching them grow into independent adults, maybe giving you grandkids to spoil.... and they opted out of that for the sake of the two children that were born first.