Should we snoop on our nine-year-old's covert internet use?

We have three daughters, aged four, six and nine. The eldest has discovered TikTok and is crazy about it. Understandably, she influences what the other two see. We have one tablet and a laptop, which we try to share fairly. We talk to them openly about what sharing means. We figure the best policy is to equip them with the tools to be critical and recognise when things are not as they should be.

However, we have noticed that the eldest is being more and more covert in her internet use. A friend suggested a monitoring app, which seems like a good idea. But I feel as if we would be snooping on them and that may backfire in the long run. What should we do?

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