DD is 18 months now and will be about 20 months with DS is born. We've talked about baby brother a lot, and she knows to come and love on my belly when we ask her to kiss or hug baby brother. She also has a baby doll and likes to feed it and give it hugs. But other than that, I'm not really sure how much "preparing" we can do for her, especially since she's so young.
Did you try and do a lot or just not worry about it and figure that she'll "get it" when the new baby comes home?
Re: How much are you trying to get DC#1 to "understand"
My DS wasnt even 13 months when DD was born, but we prepared him a lot even though I thought he was too young to understand. We got a big brother book and I read it to him every night (we still read it every night-its his favorite). I told him there was a baby coming. We even got some practice, as a few of my friends had LOs 2 months before DD was born so he saw me hold another baby. We also practiced doing "nice". He was going through a stage of biting/hitting right before the baby came, so we practiced doing nice (on our dogs, lol). Now he pets his baby sister like a dog, so I suppose that one backfired a little bit.
The first day we brought his sister home and told him thats who the baby was, he clapped. lol.
He has been really good. I think it's mostly because he's too young to understand, but I suppose what I did with him could have helped too.
I hope this is the case with DD, too! I hadn't really started worrying about it until recently as she's becoming increasingly demanding as far as our attention is concerned!