My girl is 6 years old and watch tv news and newspaper with me. For me, I think under adult supervision is fine. As you can explain what is the situation and what is happening etc. directly to him/her. I always take this chance to educate my girl to be careful e.g. crossing road, strangers, handling stress and emotions and etc. We can't shield our children from everything in real world, thus when expose to negative news, we have to be more proactive in explaining.
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