Agamemnon eliminated his wife's first husband

According to a version reported by Apollodorus of Athens, Agamemnon killed Tantalus, son of Thyestes, who was then the first husband of Clytemnestra. He also eliminated the child born from this first union before marrying the widow. The couple then had four children named Iphigenia, Chrysothemis, Laodice and Orestes.