As Charlotte Gray said, "You can kid the world, but not your sister." Not only does she know you inside out, she's also been your backbone through ups and downs in your life. She is as much fun as she is mature, and is the best gift your parents can ever give you.

3. You don't need words to express your feelings. You both are masters of telepathy.

4. Her experience in life always comes handy.

You're never too apprehensive or scared of trying something new thanks to her. She passes on her experiences and it's almost like having a personal guidebook to life.