協議離婚 婚生子女 受胎期間 婚生子女之推定 否認之訴 喪失繼承權 拋棄繼承 繼承回復請求權 遺產債務 歸扣 協議分割 Divorce by agreement Legitimate child Period of conception The presumption to be legitimate child An action for disavowal The forfeiture of the right to inheritance Claim for restitution of inheritance Debt of the estate Reversion Partition agreement