There are some people who do fine without sleep. I am not one of them. Last week I had three nights in a row where I only got about four hours of sleep each night and it wasn't consecutive hours. By Saturday night I was on the verge of a breakdown both physically and mentally. Saturday night and Sunday night I finally slept and it felt soooo good. Lack of sleep is one of the quickest ways to trigger a depressive episode for me.
That being said sleep deprivation is one of the parts of being a parent that scares me. The idea that night after night being woken up every couple of hours is almost enough to make me give up on kids. I know that sounds selfish but it is very true. I just don't know if I could be sleep deprived for years on end and not need to be admitted. I admire parents who manage and conquer this aspect of parenting.