I have three DS's, aged 14, 9 and 6. The youngest has Downs Syndrome.
Having a child with Downs is different to having a child without it, but my older two boys have been hugely different to each other anyway. I do tend to take things for granted and just accept my son for who he is, not realising how different he is to other children his age, but my nephew is only 5 weeks older than my son, so when they are together I really notice the difference. However, I wouldn't change my son for the world. He has a wonderful, outgoing and bright personality and Downs is only a small part of who he is, although saying that, withotu the Downs he wouldn't be the same person, so I would never wish he didn't have it.
I couldn't breastfeed as my son wasn't able to latch on, but I did exlusively express until 3 weeks when my milk dried up. However, I now suspect this was due to poor advice more than anything. My son also slept through right from the beginning and in fact never once woke up for a feed. He did have two holes in his heart but these were closed by surgery when he was six months old with no problem at all, it is a fairly routine operation these days.
My son does go to a special needs school. We chose this as I felt it matched his needs better. His speech is pretty delayed, he can't have a conversation but can say loads of single words and has started using several words together when he feels like it, and he does sign too. He understands everything we say to him though and sometimes suprises us with how much he does know and understand. At times, I think we underestimate him.
Everyone who knows us loves and adores DS3. He has so far retained a childish innocence which is missing in so many children these days. That is made even more obvious by the fact my older two are mature for their ages. I think this endears people to him. For example, we decorated his room the other day and put new toys in, wall stickers on etc. DS3 saw it as he was going to bed btu went to sleep as good as gold, just like usual. In the mornin ghe always wakes before us and as he hear dme in the hallway he gave his usual 'hi Mum' and then opened his door, waved his arm at his room and gave a huge 'da, dah!'. Tiny thing, but absolutely wonderful.