Board Thread:The Flash discussions/@comment-25959945-20160617213331/@comment-3423279-20160618053527

He and Iris Allen did have the twins that live in the... 30th Century or sometime like that, and the twins did indeed have his powers or similar ones.

It happened because of Time Travel stuff, turns out Iris was actually from that timeperiod or something like that and he went there to live with her after some stuff happened, that is how Bart is his grandson despite being from the 31st Century, they had kids around the end of the 30th, with Bart being born sometime in the 31st.