When someone who does not have children tells me that they are tired, I laugh. I used to be one of those people - but it was my own doing - working, going out until all hours and being involved in various other activities. I had the opportunity to slow down and sleep more or nap.
As parents of two boys under the age of 3, we have lost all ability to control our sleep. Our older son sleeps through the night and has since early on - but he is up at 6 and ready to go. Our infant son has no interest in sleeping through the night and is awake every few hours. Generally his last wake up and bottle request is around 4 am. That gives us enough time to feed him and barely get back to sleep before the older one is up.
We long for the days of being tired. We are simply exhausted and numb to what has become groundhog's day 7 days per week. There is no such thing as sleeping in or lazy Sunday. Exhaustion is the new normal. Being tired is so far in the rearview that it is a distant memory, albeit a fond one. As happy as we are with our boys, it would be that much more enjoyable if there was a bit of sleep involved.