So for the past 7.5yrs my close friend has been dating this girl. Overtime she’s also grown to be my best friend, 36yrs old. I’ve knowning for a while that she’s been cheating but everytime ive asked, I was told nothing ever happened. Her boyfriend has also come to me and voiced his suspicions but she shot them down too. They have 4 kids, of which 2 they share one is a year old and a 3 yr old. One is 8 and other is 17 from her previous relationship.

During a drunk stumble home, my 24yr old brother confessed that they’ve been seeing each other and having sex for over 4yrs and he doesn’t know if the youngest kids are his as she didn’t know either.

Bear in mind I’m now connected to all the individuals in the middle of this….what do I do? Do I tell my friend? Do I speak to my “bestfriend”? Or do I leave it….

Update:

2 other people were with me during the confession that have also seen signs that things have been happening

Update 2: just to make this clearer!

My bestfriend is the one doing the cheating with my brother!

Her partner who is clueless is one of my closest friends…