Do your grands use sound machines to help them sleep? In a generation we've gone from driving fussy babies in cars and running noisy vacuum cleaners near their cribs, to personal sound-emitting devices...and from improvised to ubiquitous. Also, we've got a walker!

The white noise podcast mentioned (there are several) is available on many podcatchers and on the web: https://www.relaxingwhitenoise.com. (This is not an endorsement, just an example.)

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