Wiring PIRs

[telectrix]

yeah, but once they are lit up, you can see what you're shooting at.

 

[w0z]

If the PIRs are powered up but not triggered and the lights are off the PIRs will consume some power whether or not it's dark so if your mother (or you) are worried about the 24/365 overhead of powering the PIRs (which actually isn't quite as trivial as you might assume), feed them from a smart plug which you can program to power them up at dusk and off at dawn. Then you can reduce the worry to only the smart plug using power 24/365...
If you get the timing right and they are powered up perhaps 30 mins before dusk you might not notice the lights coming on briefly before dusk then settling down to their real job...
If you use Alexa better still you may be able to depower and power by just shouting ...
(I assume there will be no manual override)