Jade was 8 when Alfie was born.
During the pregnancy she was really excited about having a brother, and kept on about it all the time. Then the day I had him, apparently my sister told me she was very nervous about coming up the hospital to meet him and see me and Paul. So my sister took her out so she could buy us (mummy & Daddy) a gift from her and a card, which took her mind of things and gave her something to focus on, (we never knew any of this at the time).
She very cautiously walked into the room and came and gave me a cuddle and I encouraged her to go and look at Alfie (I think she was a bit shy too) so she did, and tbh none of us have looked back since.
I was the same as you, I felt so sorry for Jade being so much older and thought she would feel left out, so I made a conscious effort to involve her in everything from the start, which included an imediate hold of Alfie to have a cuddle.
There was the initial bit of feeling left out when he was very young, but we just explained that at this age he needed everything doing for him as he is so small, but it wouldn't always be like that. We also made sure she was never left out, so I think that was more about her adjusting to having a sibling and not having 100% attention to herself.
We bought Jade a little present and said that was from Alfie, who is so happy that you are his big sister......that went down very well.
I also promised her that we would go out on a saturday or at times for a coffee on our own (without Alfie) so we could still have 'our' time together.
She has loved every minute of it, she even wants us to have a little girl now. So I really think your LO will be great hun, I truely was worried, but she absolutely dotes on Alfie, and he gets all excited when she comes home from school or when he sees her first thing in the morning.
At the moment, they both spend a lot of time crawling about on the floor racing, which is ace as it has Alfie in hysterics and it is keeping her busy and is all good for their relationship.
I am sure you will have as much enjoyment watching your kiddies together, as will your daughter having a sibling around. x