Why am I so wrong?

I get mad when I hear that 12 year Olds and 13 year Olds are already having sex. Getting naked in social media for likes. What happend to enjoying being a child? Why is it OK for kids to have sex? I express this to a friend of mine and she stopped talking to me because she let's her daughter go out with guys already at 13 but I didn't know that, I didn't say it maliciously. Why am I so wrong?