What is the ruling regarding a wife's refusal to embrace and kiss her maternal uncle and her refusal to receive him in the marital home during her husband's absence?

Kissing unmarriageable kin (mahram) such as one's mother, sister, and daughter is permissible if it is out of mercy and affection. The same applies to one's paternal aunt ('ammah) and maternal aunt (khālah) if there is no fear of temptation (fitnah). There is also no harm in kissing one's niece (daughter of a brother or sister) if she is young.

However, kissing a young woman or a married woman who is not unmarriageable kin is not appropriate, due to the fear of arousing lust or the whispers of Satan. If a man and his niece are both young, kissing and embracing her is an abominable act and a likely cause for arousing lust and evil.

As for kissing non-mahram relatives such as the daughter of a paternal uncle ('amm), paternal aunt ('ammah), maternal uncle (khāl), or maternal aunt (khālah), it is forbidden because they are considered marriageable (ajnabiyāt).

What is prescribed upon meeting is to offer salaam and shake hands. Upon returning from a journey, embracing is legislated. As for kissing on the cheeks, there is no evidence for it in the Sunnah.