Supergirl is now on her fifth screen incarnation
Helen had only the one film, she was Chris Supergirl, they never filmed together
Dean never had a Supergirl which was a wasted opportunity
Brandon never had a Supergirl, she would have been the same continuity as Helen
Laura was Supergirl in Smallville, an interesting take for that version, and the sexiest Supergirl we've had
Melissa was Supergirl for her own show, her version of Superman played by Tyler came from her, not the other way round
Sasha was Supergirl for the Henry Superman, though they never appeared together, the dark haired, darker version of Kara for this universe, a pity we never saw her realise her potential
Millie is the new Supergirl for the David Superman, again a different take, party girl, drunk, attitude, very different from how Melissa portrayed her in the show