Trouble Getting The Kids To Sleep

I’ve always had trouble getting my kids to sleep. I found this YouTube channel named 6666meditation and I started playing meditation and lullaby music in the evening times after dinner. It seems like the calming music relaxes them and they are in bed by 8pm every night. Before I started playing the music, they’d stay up until 10-11pm playing video games or watching tv. Why didn’t I think of this sooner?