with [without] a person's blessing＝with [without] the blessing of a person🔗⭐🔉

with [withut] a person's blssing＝with [withut] the blssing of a person 人の承認を得て[得ないで].

研究社新英和大辞典に「with a person」で始まるの検索結果 1-1。