Is expiation required for an oath sworn upon one's son to take a bath, but he did not do so and went to sleep instead?

Since the questioner swore to do something and it did not happen, she must offer expiation for breaking an oath (kaffarat yamin). We advise her not to be hasty in taking oaths, for Allah has commanded their preservation, and frequent swearing is prohibited. If she did not intend the specific night the oath was taken, and he bathed himself, then there is no breach of oath for her.