About the only time PD symptoms aren't active is when asleep. That said, the problem for many is getting to sleep and/or staying asleep. Some nights my husband can't get more than a few hours max, and of the 14 years since diagnosed this has been the case for over 12 years.
Not knowing how much you have read up on what we call 'the dragon', PD is a very complex disease. There are so many different symptoms that each individual can experience, but unlike most other diseases there is NO one pattern. No two individuals will have the same symptoms, in the same order, for the same period of duration. For a short while my husband had problems with restless legs - drove him nuts. RLS runs rampant in my family and all of us have difficulty explaining it to our spouses - now I am the lucky one, as my hubby truly 'gets it'!!! When the RLS quit bothering him I was a bit jealous but also grateful for him, as I wouldn't wish it on anyone.
Read up on PD, it will help you see that there are times when your mother's actions might seem odd but in fact it is another of PD's nasty issues playing havoc with her life.

Sleeping is the best part of the day. I take Melatonin 10mg before bed and only get up twice during the night to use the bathroom and then go right back to sleep. No tremors.

Sleeping stops tremors and dyskinesia because our bodies trip into relax mode but most of us don't sleep particularly well.

I would consider asking your doc about Deep Brain Stimulation. Depending on age and eligibility for Medicare, it could be an answer. It isn't without some risk, (such as speech impediment for some) but for my wife it has been a godsend.

My husband has tremors all the time, but i agree, when he's sleeping, they subside. But when sleep lessness happens, it makes for long, restless nights and the next day is very difficult. Shaking also gets worse when he hasn't had good rest and enough sleep.
This is the reality of the disease.