Why do babies fight sleep?

I'm not trying to be funny...I just really can't get my head around why a 6 month old would fight sleep so much. I really wonder if they are capable of thinking that they are going to miss something or what?

DS was up from 2am to 5am exhausted. He wasn't even crying he was just up making noises - he would eventually fall asleep for a few minutes and then would wake back up again. He was so tired you could see it, but it was like he couldn't relax to fall asleep.

Of course, now that we have to be somewhere he is still sleeping and I am exhausted!

Re: Why do babies fight sleep?

I know what you mean... DS is 3 months. He's pretty good at going to sleep around 7:30 - 8ish, but he'll look at the mobile and smile then look around the room for me. Once he finds me he smiles a lot. Like he knows if he's cute I'll let him stay up. LOL! He usually goes to sleep soon after then gets up at 4 AM every night and wants to play. After a bottle he go to sleep for only another hour or so and by 6 to 7 AM he's up and ready for the day.