You can say:（うちの）両親がご家族の皆さんによろしくお伝えくださいと申しておりました。 [(uchino) ryoshin ga gokazoku no minasan ni yoroshiku otsutaekudasai to moushite orimashita. ] uchino= my ryoshin =parents (go)kazoku = family *go=> to be polite minasan = all, everyone yoroshiku otsutae kudasai = please say hello to (in polite way) moushite orimashita = said (in polite way) If you have other questions, don't hesitate to ask me.