Well, I have TWO high needs kids. My first DS was an angel baby. SO good. Never cried, slept well (as long as he was in his swing), but was a fussy eater. Never wanted to nurse and was ho hum about the bottle too. He is 5.5 now and has high functioning Autism. He was EXTREMELY difficult for about two years between ages 1 and 3. He is now our "easy" child.
BECAUSE DS was such a good baby, as soon as he turned one, we started trying for #2 (we always said we wanted two kids). I got pg right away. During my pg was when DS1 started going downhill, behavior/needs wise. DS#2 was born a month premature, had some issues and had to be in the NICU. As soon as we brought him home, it was like we had the son of the devil (no joke). He was SO intense, always either crying or sleeping. He actually slept alot, but he was very clingy to me, always. He's four now and has been the MOST DIFFICULT child imaginable. He has been in therapy since 16 mo old for behavioral issues as well as a major speech/language delay. He still cannot talk very well or communicate well, so he has a VERY short temper, is demanding, controlling, stubborn, angry a lot, defiant. I could go on.
I love him, though, with all my heart, and am glad that my older DS has a sibling (think that's good for Autistic kids to have, for the social aspect of it).
BUT, I have to say, if he had been my first, I would have probably been done! I have had to find a way to deal with him because that's just what I was dealt. Thankfully, my older DS is extremely sweet and good natured, so they balance out well.
I'm not gonna lie...there were MANY days I questioned having DS#2, and not so much because of how HE was, but because in the first two years, when my older DS was very difficult (before he was diagnosed and we didn't know what was going on), and DS#2 was ALSO difficult, there were many times I didn't know how I was going to make it through the day.
Looking back, and knowing what I know now, I would have still had them both, but we have stuck to our "2 kids only", and got DH fixed when DS#2 was only a couple months old.