My sleep pattern has changed over the different periods of my life.
When I was young (late teens/twenties) I could sleep anywhere - and did so in some strange places. Once I had children, my sleep was much lighter - (I suppose always on the alert for a cry). I learned to be able to doze off whenever the opportunity presented itself, but got used broken night. I also fostered new-borns, so the 2.00 am feed and the 6.00 am one was a normal part of my life.
As my children went into their teens, I began a better pattern of night=time sleeping, but was never fully asleep until they were all back home at night. And, always, the slightest noise around the house would wake me. Normal for Mums.
As time went on, and children all left home, I returned to normal 8 hours a night, and was always able to fall asleep quite easily once light was out and i was tucked up in bed.
As I grew old(er), I started the normal age related thing of needing to get up for loo once or twice each night, but went back to sleep each time quite quickly. Also, as an ostomist, often needed to empty my bag at those times.
Over the past few years I have developed a mild form of insomnia. I would be tired, go to bed as normal, and then toss and turn and not fall asleep. I found that if I actually got out bed - usually went into my Living room in my riser/recliner chair and turned on tv to watch something quite boring (found shopping channels quite good for this), then would start to doze off and return to bed and would fall asleep.
Now I use a CPAP machine each night, I have started to go to bed much later, always get up at same time, no matter how good or bad I have slept. One of the good effects of this machine for most users, is to cut down the number of loo visits required during the night. For the past few years have been so tired all of the time (Sleep apnoea finally diagnosed), so would spend so much of my waking hours falling asleep - now with CPAP, only need a short 45 minutes sleep after my lunch. In my mid-80's feel that is not too bad. So, most nights I have about 8 hours of sleep with one trip to loo. Still get a bad night (about every 5 or 6 days).