How conveniently they forget
DH was surprised by a casual reference by DS19 to OSS19 and something that DHs super, special, angelic snowflakes would never, ever do. Yet DH had been told a few months ago that OSS was doing this thing, I think by OSS himself. DH conveniently forgot/ignored it and his physical reaction now made it obvious he had buried his head.
This isn't a situation where OSS should be banned from the house or anything, just a typical teen-adult thing. I'm in observation mode and I find it interesting and kind of sad how quickly DH erases things he doesn't want to know and gets surprised by them multiple times.