[@MrDidact] that's a possible, though if you really want to keep Don and Dawn it could alternatively be Dawn who gives birth to Bart and a whole legacy of Thawne being all sneaky triple agenty, would kind of bring the rivalry to the current Flash level rather than  just the top of the pyramid. I will probably, if we're going with Don and Dawn being active not focus on them as much simply as I don't know them as well as I do Wally and Bart.