One area that usually gives parents parenting anxiety is talking with their children about sex and sexuality. Some are so nervous or dumbfounded that they simply don't bring it up at all.
Here is a great, 5-minute video from the Church of Jesus Christ of Latter-day Saints ("LDS" or "Mormons") that you can watch to give you either a good vocabulary and approach in how to talk about this with your kids. Or, it might even be good to watch with them and then talk about it after.
Some children are exposed to pornographic images as early as 3rd grade. If they don't hear about it from you, they will likely not bring it up with you. And secrets can yield not only distance in relationships but bad habits and misperceptions about what God created to be beautiful.
https://www.youtube.com/watch?v=F3yS58GAiPg
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