So we already knew Sej was the warmother of her tribe after taking control of it. What we didn't know is if she had taken any oaths. She is far more traditional than Ashe, and the new story confirms she has at least a few bloodsworn...the question then is, do we think she has any children yet? The reason the freljord is matriarchal is due the the extreme importance placed on children.
While her role as a brutal horde leader is definitely what would be focused on, there really is no characters where being a parent heavily factors into their story. Varus is now a darkin
Darius is I think the only other champion we know of who has children