Although he was originally an illegitimate son, he became a heir in June 1744 since his younger brother Yoshiatsu AOYAMA, a legitimate son of the same age as he was, was disinherited due to weak constitution.
庶子であったが、同じ年で弟の嫡男・青山幸篤が病弱を理由で廃嫡されたため、延享元年（1744年）5月に世子となった。