Wow, I envy you. I always wanted to foster or adopt medically fragile or terminally ill kids. See, I lost a baby to a genetic condition, and know that I can survive losing a kid a whole lot easier than they can survive not having a family.
But life has just got in the way of that - and Wyoming isn't a place we could do it anyway, we were too far from medical services.
Now, I'm pregnant instead, so I get to be the gray haired mama whom everyone thinks is the grandma. I sort of HAVE to think that there's no such thing as being too old.
My older sister is heading to Ethiopia in two weeks to go through the court processes on two children (both under the age of 2), whom she should be able to pick up sometime this summer. She's 50 in April, her husband is 57. She says that it is hard, and a hassle, but no other way to give kids a home, so she keeps doing it long past the time when she thought she'd stop. At one time she said, "When my kids have kids, I'm done." She now has three grandkids... And the two kids from Ethiopia will be her 12th and 13th children.
So kudos to you, I'd love to be in your shoes.