Can someone explain to me how two computers can each be looking at the same file and seeing different things?

I have a two computer setup and was checking out teh problem of the wrong name being in the "Return to..." arrow on the "Report" page.

I open the same online tree on each computer
I pull up the same person's overview on each computer
I click search historical records from the over view pages
I get identical results-except there are different names in the return to arrow- neither of which match the person on the overview page.

See attached screen shots