To the rest...there is little I can say that I didn't say before...please read the link below and think of your own memories of her...or, of siblings you, too, cherish.
To have a sister is to have a built-in best friend...the most honest reflection of yourself...a keeper of memories...the one you learn to fight with...the one you learn to share with...the one you learn to make up with. She knows your secrets and will protect you like no other. But she will also remind you where you came from and keep you grounded in ways no other can. Our hearts are always connected and forever we take care of each other.