While others their revels keep,
I will watch over thee.
They struck me because, in ten words, they sum up the things that good parents do, and the sacrifices they make to do them. As they see many of their childless peers spending all their time and money on their own pleasures and advancement -- travel, undistracted education, possessions, careers, promotions, and the rest -- parents choose to conceive and bear children, make good homes for them, play with them, give up career advancement to keep from having to uproot them, worry over them, protect them, teach them, read to them, pour thousands of hours helping them grow up in every way, and then endure the pain of letting them go.
And yes, often, just quietly watch over them as they drift off to sleep.