嗣
シ, あき, つかさ, つぎ, つぐ, ひで
heir, succeed
JLPT1 G7 S13 F2310
The left-hand element is 口 mouth + 冊 (bamboo slats) → oath designating an heir, written upon thin strips of bamboo. 嗣 adds 司# administer → *heir* who succeeds to and administers an estate.
[Full Kanji Etymology List]