You know how some martial arts can resemble or have elements with other martial arts? IE. Shotokan & Shorin Ryu, Shotkan & TaeKwonDo (sort of), Wing chun & JKD, Jiu jutsu & Judo, etc.

But are there ANY martial arts that is a sister to throwing doctrines of Aikido? All MAs I know are either a grappling cousin or a striking cousin. But I don't know of any MAs that specializes in throwing the way Aikido does! Is Aikido supposed to be unique or something?