When my kids are asleep, they breathe with the ratio of the golden ratio. You can use this music to help your kids relax. You may also make them aware of their own breath. If they are able to breathe with the music, thats good, but do not force them. Just make them aware the music has a breathing pattern. The slow tempo and the safe ambient sounds will also calm them down.
Or just play it in the background and see if anything happens to the mood.
These tracks are just available on this site.
After completing the purchase, you'll get an instant download link sent to your mail. Use this link to download the mp3 file(s) within 72 hours.
Android users can download the files directly to their phones.
iPhone/Ipad users need to download the files to a PC/Mac and transfer them to their device via iTunes.
I wish I could offer an easier way to transfer the files to your devices, but I don't know how.
Headphones / earbuds are recommended for best experience.
Dropbox and iCloud can play mp3 files and are possible workarounds to save files to your Apple devices.