Cats are crepuscular, which means they're most alert at dusk and dawn, the prime hours for hunting in the wild.

At home, they're driven by the same burst of energy in the early morning. It's all good and normal, but if you get up to feed them when they start meowing in the wee hours, you're reinforcing the behavior. Instead, give them playtime before you head to bed to help wear them out, and ignore any overnight ruckus. With patience, your cats may eventually learn to pipe down.