If it were me, I would definitely think that women know what women like, so your sister's mother-in-law is afraid that the necklace her son bought won't suit your sister's mind and wants to give it to your sister as a gift to improve the relationship between mother-in-law and daughter-in-law. Who said that buying a gift must be given by a boyfriend? I often receive gifts from my boyfriend and mother. On the bright side, why push yourself to the wall? People just like to complicate simple problems.