Retired from teaching school music/band 14 yrs ago.
My first grandchild was born 6 months later and I had a wonderful time babysitting her a couple of days a week until she began school. Her brother soon followed.
Try to golf twice a week, which in northern CA is very doable.
Musically I have been playing with trio and using BIAB for solo performances. That usually amounts to 6-8 gigs a month.
And oh yes those doctor appointments do occupy more and more time although I feel great at 73.