There is no "back" to where you were button (only the page before / after button).
I really want a mouseover with text box popup; mouse over text/textual popups?
The problem I am having is if you have a text link to send a child (8-10 yrs old) to the back of the book for enhanced information on a subject word "how do you get them back to where they were reading." There is no back button. Acrobat Reader DC has a "back button" but not for links.No, that concept isn't really a supported PDF construct.
That said, one likely could make something akin to a pop-up using Acrobat and hidden layers that can be viewable upon a mouse-over event, but otherwise hidden from view. It would take a lot of manual work, though, and likely not usable using any pdf reader other than Adobe reader and likely not on mobile devices.
I do not want dumb down the vocabulary in the children's book just because there is no back button to a glossy, nor the original thought of a simple text hoverer to solve such a simple thing.