I tried googling around after encountering the problem and found a few people talking about it from as far back as June (as well as a month ago on Reddit) but wasn't sure if it was reported here yet. Upon entering Sylvan Glade either by a random NPC invite on the phone or the tree itself all sims are given an instant +10 uncomfortable/nausea moodlet and continuously throw up. This continues until they leave at which point they're fine and the moodlet is gone. I saw someone say it happened to them as well on Sixam after being invited by an NPC but I don't have any packs to test that for myself. Hope this can get fixed soon, I've had to disable NPC invites for the time being since most are to Sylvan Glade and my sims are just puking constantly while there and I have emetophobia.
For the SOL Mod its annoying that other sims beside households will have there period because they always smell bad.