Twos does have bidirectional linking through the use of sublists. If you nest a list inside of another list (lists can be nest infinitely and in as many days and lists as you'd like), you can navigate into a sublist, and you will have a reference back to the parent list. It's not bidirectional linking as you may be accustomed to, but it accomplishes the same goal and we will add proper bidirectional linking in the the future