I feel like most Zelda games begin with a sleeping Link. A Link to the Past, Link's Awakening (lol), Ocarina of Time, The Wind Waker, The Minish Cap, the DS games, and even Skyward Sword come to mind. The beginning of Twilight Princess always felt weird to me because it
didn't begin with a sleeping Link. Besides that, I think it's fair to assume that all Links are sleepy, not just toon. Perhaps, along with courage, a silent nature, and a green suit, each Link also inherits the quality of laziness.