Why does time move so quickly?

My little girl is now 2 and a half.. and Jay is 8 months old! Time seems to have flown by. Jay is saying "Mama" and is a complete mama's boy... he follows me around and tries to climb up on me and loves me to hold him and grins whenever I kiss him. I love every second of it. Especially after seeing him suffer through RSV and starting a busy new job.. I try to appreciate every minute with both of them. Adriyanna's favorite book is about Leonardo, the Terrible Monster (from auntie amy) about scaredy-cat Sammy and includes a big hugging scene. My sweet ones are so wonderful.