Reading a letter from a friend and finding instead of the normal gushings about boys and school, it's like reading your own personal thoughts written in someone else's hand. Visiting your old high school and noticing that all the students there not only look really young, but were actually in third grade your senior year. Being a bridesmaid in your best friend's wedding. Staying up hours later than you had planned writing letters because you want to give someone the same joy that their written words give you. Having a child not your own look at you and say "I love you with all my heart" and know that they really mean it. Holding the newborn baby belonging to the first of your friends to get pregnant. Realizing that somehow, while you weren't looking, you passed from childhood into adulthood and there's no going back.