My oldest son is very difficult to wake up in the morning. I’ve tried having him set an alarm clock to no avail. I am usually fairly busy in the mornings and it always irritates me to have to stop what I’m doing and go upstairs to wake him up yet again. Plus he is never happy when I wake him up.
I accidentally discovered the best way to get him to wake up and not wake up grumpy.
So now letting his beloved baby sister do it is definitely working for me.