Quote Originally Posted by ally66 View Post
Are the last three threads with Sara Missing? Mine is locked with "Complete Previous Threads" message - even though all previous threads have been completed.
Those are part of the "back to school" event between her and Mrs. Rider. You need to complete both of their chains prior to that point before they open up, then they start alternating between the two. It was kind of explained in a news pop-up when the event was released, but now there doesn't seem to be anything explaining it which seems like poor design to me. Anyway, move on from her for now and come back after finishing all you can with Mrs. Rider.