Chai

From Yin Yang Yo! Wiki

Chai is Ti's older brother and Master Yo's father figure. He and his sister taught Yo. They where very poor like Yo, so they trained him in a similar manor to how he trains Yin and Yang. Finally they died at the hands of Eradicus when he wiped out Woo Foo. Somehow he and his sister were there when Yin and Yang where born.