Heart problems and autistic traits are probably the best known ones but are just the start of a very, very long list.
As a baby/toddler the developmental delay is already evident and as as they grow, the gap gets wider. DS is 6 and still in nappies. He has a very health six-years old appropraite diet, you try cleaning those poo filled nappies in a diasabled changing room that doesn't take his needs into account.
He has a language delay and I can just about hold a conversation with him, no-one else can. If he gets lost he couldn't tell anybody anything past his first name. Think on that one!
In saying all that, he is in mainstream school having done three, rather than two, years in a mainstream nursery. He is coping well but as mentioned has very poor communication skills and also very, very poor fine motor skills so he still scribbles on everything and can't colour in anything.
I could go on and on but I think you get the idea. There are many who may have it easier and certainly lots of people who have it a lot worse but easy it is not!