User blog comment:TimeShade/2015-2016 Season Community Choice Awards/@comment-26618197-20160921171804/@comment-26618197-20160921175408

And Barry plays off of Supergirl as someone who's been through similar things in their lives as not just crimefighters but as kids

Both lost their parents even if under very different circumstances

Both were raised by another family and are very close to their adopted parent

Both had to learn that they couldn't save everyone the hard way

Both lost their powers for a while again under very different circumstances

and both were made super angry and that anger got worse over the course of their respective episodes

In fact during the next couple crossovers I'd like to see how his, J'onn, and Superman's relationship will be considering that with Kara his and J'onn's approach towards helping her learn how to be a hero is more hands on while Superman prefered to let her figure this stuff out alone with some helpful tips and support