How to handle toxic online behavior from relatives?

Assalamu alaikum wa rahmatullahi wa barakatuh, dear brothers and sisters. My wife and I have recently come across some troubling behavior from a few of our nephews on her side. I personally don’t use social media much, but my wife and these young men have Instagram and Facebook, and they all follow each other. I told my wife years back that I wasn’t sure it was a good idea, but it’s been their norm for a long time, so I let it be. Lately, a friend of my wife was getting harassed online. After digging into it, my wife and her friend found out that three of her nephews were involved. They’d connect with friends of friends and leave nasty comments several times a day. I asked, “Why not just block them and move on?” but this has been going on for a while with different accounts, and the link is that they were always on my wife’s friends list. Honestly, these fellows aren’t being subtle, or maybe they just don’t care. The nephews are 31, 27, and 20-they’re not kids. They’re grown men, but my wife had a hard time seeing that until this wake-up call. Her side of the family isn’t really practicing Islam. I’m already the odd one out because I often give gentle reminders about faith. My wife insists that I should speak up. The boys are from two different families-my wife’s two brothers-in-law-and two of them are somewhat in touch with their dad. I tried talking to a couple of them a while back about some things I noticed, like the type of music they listen to and the way they speak about religion. It only got me dirty looks and cold shoulders. Now, I don’t think it’s my place to correct them. I can’t manage seven nephews when I barely have a bond with them, let alone when their households aren’t oriented toward Islam in the first place. Any elders or wise ones in the faith, please share some guidance. I don’t want to neglect my family or miss the chance to fulfill the duty of reminding others about the Qur’an and Sunnah.