As a mom, I am tired all. the. time. OK, maybe not all the time. I think I'm fully energized for a few scant minutes around noon, but that's about it. When babies are born, they wake up all the time and you wonder, When will they sleep through the night? You think that once your baby starts sleeping more than three hour stretches, you're in the clear. Woohoo! They're sleeping through the night! This is great.
And their growing developmental skills which compel them to wake up at night so they can finally build that block tower more than three blocks high.