Curtis welcomes sleep. When you lie him in his crib, especially at night, you can see his body go limp, his eyes roll back, and I am fairly certain he lets out a sigh of welcoming relief. See, like most NORMAL people, too must stimulus overloads little Cucky. He needs downtime to reboot. And he enjoys it.
Brock, on the other hand, may have inherited my distaste of sleep. He has fought going to sleep for the entirety of his tiny life. You see, too much stimulus, well, stimulates him. He has a very hard time winding down. He is absolutely excited and passionate about life. He has no time to slow down. He does not want to miss a thing. Though, there have been a few moments that he has worn himself to complete exhaustion and literally begged to go to bed. Oh, how I love Summer.
Niether method is right or wrong. Curtis is not lazy for enjoying sleep, and Brock is not smarter for wanting to experience more. They are just different. Thankfully, they do share one sleep habit...when they are down, they are DOWN. Those boys exhaust themselves each and everyday. They need every bit of 10 hours of sleep, sometimes 11 or 12, and they take it.