Photographing soul-possessing creatures is Haram (prohibited) and a major sin. Accordingly, neither your wife nor anyone else has the right to keep such pictures. In addition, considering her brother-in-law as her own brother does not permit her
to keep forbidden pictures. Being her brother-in-law does not make him a Mahram (an unmarriageable relative) to her and does not permit her to keep his picture or the picture of any other person.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.