My daughter is fairly easy, she spoke at an early age so she is pretty vocal about what she needs/wants. Only recently did she start crying when she wants something rather than asking. It could either be her last set of molars coming in OR it could be the fact that she sees that when the baby cries, he gets attention, or maybe she is just going through an emotional time. Who knows.
All through my pregnancy I wondered things like: How am I going to go grocery shopping? How am I going to get in and out of the car with TWO kids? What is bedtime even going to look like?
My biggest worry was the car. I kept thinking, "What if I am putting the baby in or taking him out and she runs?" The only answer I have to this is that you have to figure it out. I'm lucky that my daughter understands so much because when we leave daycare and I am clicking the baby in, she waits by a big wooden tiger outside of the daycare but out of the way of cars. Only once has she tried to make a run for it and she was very sternly reprimanded. If we are leaving a store, I may just throw her in her seat, shut the door, put the baby in and then go back and buckle her in, just so there's no way she can run or wander. I can't imagine trying to do this with three.
For grocery shopping, I wrap him in my MobyWrap, which I usually put on before I leave the house, and she will usually walk beside me or sit in the cart...Usually.
Now for bedtime. He is still so young that I can just feed him at about 7:15, put him in the bassinet and he mostly falls asleep on his own while I give her a bath and put her to bed. They both still do wake in the night so some nights that's a really fun time. I'll keep you posted on bedtime with two as he gets older!
All in all, she loves her baby brother. If he's crying she will pat his belly and say ,"It's okay buddy." She loves when he accidentally bumps her or if he gives her a big smile. I think she is just starting to realize that he IS her baby brother and he isn't going anywhere.