A dear friend of mine has a special needs 5yo. They are still not sure what is wrong with her- delivered healthy, but started having seizures at 3 days old. She has had dozens of seizures each year. She cannot speak- makes some noises. They don't know what she hears because she can't communicate. She can walk with a brace, but mostly in a wheelchair. IT IS EXHAUSTING.
They quickly realized they would need to have several more childrento be sure daughter is always able to be cared for by a family member, even after parents are gone, because she will never be independent. She will probably always be in diapers. Never be able to work or have a friend or go to school. She is quite frankly a tremendous burden on their family/ they love her so dearly and their 3.5 year old is such a sweet sister to her and so helpful and grown up for a 3.5 year old. But she will always be a burden.
Think carefully through your desire to adopt a needs kid. It is wonderful, admirable, and commendable....but please thoroughly think through how this child will affect your life for the next 60-70 years as well as the lives of your natural children. Are you prepared to have a child permanently at home living with you & hubby for your entire marriage? Who will you leave your 40 year old kid with when you & hubby want to go to Europe for your 65th bdays? Will you force your other adult kid's & their families to "babysit"? Will you hire a sitter? Do you want to change diapers every day for the rest of your life? Will you have enough money/ insurance to keep paying extensive doctors bills after you've exhausted your lifetime policies? Will you have enough money saved uPon your death so that needs kid is always provided for? What expectations will you have for your bio kids' role in the needs kid's childhood and adult life?
It seems like it would be easier on you if you had 1-2 bio kids first and then adopted a needs kid once your other two were ages 5 & up. Then you have 4 sets of hands to help with the needs kid. Remember, if the needs kid comes first, they will be of no/ very little help when you have babies....that will be exhausting & stressful!!
Lastly, I don't mean to sound patronizing, but teaching a needs kid and living with one are two completely different animals. If you & hubby can, offer to babysit one of your kid's for an extended weekend while the parents go out of town. See if you're still up for it after being "on" for 72 hours with no break. Multiply that times 100 times 60 years.