They mentioned a new character recently, it's a lioness cub called Zuri. She's supposed to be Kion's friend and a member of the Lion Guard. Rumors went around saying that she's the lioness cub on the front cover of the "Can't wait to be queen" book they're gonna release next year.
http://lionking.wikia.com/wiki/Can%27t_Wait_to_be_Queen
I wonder however, if she'll end up being Kion's possible future love interest/crush? I think that'd be adorable x3!
Her name even means "Beautiful" in Swahili, which would be appropriate if it ends up so.