We were blessed with DIL and 1st GD living with us for 18 months. The memories are so special. We did babysit when DIL worked part time in evening once we were home from work, and weekends. Now have 2 GD and they to far (WAY to far) away. I sometimes feel jealous of those that who can their grandbabies all the time.
I don't know if I could do 40 hours a week though.