How to convey interaction between two cells

I am working on a project that includes designing some behaviour for a web data grid. I run into a question described in the title. Below is a screenshot.

The editable input cell is the one with blue pencil icon, and the one will change accordingly locates on the right side, surrounded by a illuminated border along with a light blue overlay on top. The idea of this design is that when a user making a data entry/adjustment, the other cell will be highlighted temporarily (flash for a sec and then fade out), and the content will change at the same time (request from client).

I was wondering if this approach is strong enough to indicate the relationship between these two input cells? Also this makes me wondering the size of user's eye focus area when they are doing a data entry. I notice that in a text-area entry, I tend to only focus on the text area itself. Thus in my design, though the related input cell is somewhat highlighted, will the user "notice" that? should I move the related cell next to it to enforce this concept? Or should I discard this and come up with another idea? Many thanks.