Is this legal? Could someone sue?

[Joe]

So this person asked someone else not to post their location or age on twitter for privacy reasons. So a week later that person posts both age and location an also insults with untrue things such as saying they don't know what they are talking about and swearing. Could the person sue the one for posting this content. Both minors. Is this defamation? Invasion of privacy?
I did not do this but something like this hits close to home.

Thanks