Q: My child found a lost item. Is he responsible for hashavas aveidah? Am I responsible? If there is no siman, does the item become his?

A: Chazal instituted that if a child who is supported by his father, even if he is a bar mitzvah, found an item without a siman, his father is entitled to it. The reason is to avoid animosity with the father who is supporting him. The father can allow the child to keep it, though (C.M.270:2).

Therefore, if the child found something requiring declaration, some say that the father becomes responsible for hashavas aveidah. If he wants to train his son to declare the aveidah, the father should make sure it is done properly (Hashavas Aveidah K’halachah 9:3-4).

If the child is not supported by his father, an aveidah without a siman belongs to the child, whereas an aveidah with a siman should be declared. If the child is bar mitzvah, he has a full obligation of hashavas aveidah; if under bar mitzvah, he has a chinuch obligation, as with any other mitzvah. However, some say that if the owner subsequently had yei’ush, the young child can keep it (see C.M. 349:3; Pischei Choshen, Aveidah 2:8, 9:26).