Princess Laethwyn is one of the supporting characters in Batman: The Brave and the Bold.
She is voiced by Gabrielle Carteris.
Princess Laethwen, daughter of Caellich, is ruler of the Katarthans of Morlaidh on Earth. She fell in love with Ray Palmer and wished to marry him. Chancellor Deraegis disapproved and instigated a coup to take over Morlaidh and the world. Batman, Aquaman, Ray Palmer, and Ryan Choi saved the day. Laethwen bestowed her people's highest honor to the trio.
- Sword of the Atom!
- Out of the Justice League, Back into the Outsiders! (mentioned only)
- Clash of the Leagues! (mentioned only)