Bug causing romantic relationship between brother and sister

After today's update I created a brother and sister sim to try out the freelance career, and they made it thru a whole week then suddenly they were listed as having a romantic relationship.  This is obviously a bug and not an okay one, I did delete the game, sorry I don't have the info you may need anymore, but it had to go.  Hope this helps still, thanks. Also in the same game, when my sims were invited to either a talent night or to a festival instead of going to the place invited, they would show up at a residence, not even one the sim doing the inviting lived at either.