Yes, about the older kids being interested in baby development. My 10 year old ds had been adamant that he didn't want another baby in the family, and so I was worried about him not being happy at all and scared to tell him! (DH had a problem that I was keeping it secret from only him so HE told him). I think he was a little upset at first. But when I went in for my pregnancy confirmation with ultrasound appointment, they sent me home with a copied page that said "your baby at 9 weeks," and I left it lying on the back counter. My son came in to wake me up the next day, and said, "I didn't know all that stuff about such a tiny little baby; that's cool." And he has been accepting and interested since then. He even surprised me by saying he would rather have a sister (because he already has a brother).
Our current "baby" is nearly 3, and I have been feeling a lot of pressure to get him both potty trained and out of my bed before the new baby comes, but then I decided not to stress or force that issue. Now I know I shouldn't try to crowd him out of being a baby! He is growing up, and I bet he will be using the potty at least by July, but it's less likely if I put pressure on the issue, I think. The co-sleeping issue is still a concern, but like I said, I feel like I shouldn't stress about this now. I will be buying him a new, bigger bed (the bed in his room is still the crib mattress), and I am also thinking about letting him and his older brother co-sleep instead, although I have reservations about whether that is a good idea.
We will take the 2.5 yo to the gender ultrasound; other ds will be at school. I don't like to take him to regular appts and go alone to all of those, but Daddy will come just this once for that u/s. I will be birthing at a hospital, and had planned for both boys to be at my mom's house during that time, but I am now thinking of maybe having them and my mom at the hospital during labor. We may make that call when the labor actually begins.