It has made us take the decision to not have a third child.
DD is 5 yo and only started to go to sleep by 9.30pm once in school. DS is 2 yo and has only just started to sleep through, but only goes down after 10pm. We have no time alone as my DH is so tired that he frequently falls asleep during story time and DD wakes him up to tell him that she has finished her book, would he like to hear another!
They both used to sleep heavily during the day though, so at least I could have a bit of downtime then...
DH gets up at 5.30am to go to work, I am an extremely light sleeper, so my day starts too...
DD has not slept for 12 hours a night more than 5 times in 5 years, many times only having less than 8 hours to go to school on... Yet she is lively and bright.
DS gets very grumpy before he falls asleep but is always cheerful on waking.
These positives make up for my absentminded ness, my tendency to shoutiness in stressful situations (trying to get them to leave the house on time for school etc.) and the feeling that I have aged 10 years in 5 and am now haggard and hollow eyed with tiredness, rather than looking young for my age (which made me preen, secretly).
I'm enjoying the time before school starts again as there is no enforced routine around school run times, so can recharge my batteries. I'm feeling less like a zombie and the physical feeling of brain fog is lifting.
Hope all the other posters had a restful sleep last night and feel more positive today...