A.G.
My girls are 2 years a part. A couple of things I did...
1. I made sure that when we brought new things home for the baby we also brought things for her. We did not go over board, things like a coloring book, her favorite snack. We always paid attention to her and showed her what was for her before the things for the baby.
2. We encouraged her in the fact that she was the big sister. We made t-shirts that said big sister, and a onesie that said baby sister with Iron on transfers. We also read a book often about being the big sister.
3. We included her in things like picking out things for the baby. We let her go to baby's r us and pick out a back pack, and let her pick out a baby bag, and threw away her diaper bag. She was the big girl and we packed her a big girl bag when we went out, and we packed the baby bag together. Her and daddy brought the baby bag to the hospital.
4. We allowed her to hold her abd help with bathing and even let her pick out what the baby would wear, and what blanky the baby would take.
5. I think this is the most important. We gave her special time. When the baby was sleeping we would play play doh, or go in the pool. Do things with just her. Daddy would take her to run big girl errends on Saturday. The baby would go to bed before her, and we would read to her at bed time. If you make each child feel special, and instill in them, they can have attention with out acting out it is always a good thing.
The only problem we had was if we tried to ignore the baby sister would be so mad. One morning the 2 year old was watching Barney, and the baby was in the swing crying while we were getting ready to go to church. The 2 year old got the baby out of the swing and was dragging her down the hall so that we would take care of her. She has been a great big sister.
Good Luck.