They are growing up so fast

Our kids are growing up way too fast. Last night they went swimming in the lake. All of a sudden, Brayden stuck his face in the water and actually swam about 5 feet with his legs and arms just a pumping. No one had showed him what to do or even told him to do it. By the end of the night both boys were swimming with their faces in the water for a good distance with life jackets on of course. I don't want them growing up this fast. I wish I could look away and they would stop, but I don't want to miss anything either. Unfortunately I didn't have my camera with me, but I will next time.