If there is nothing dubious about the family gatherings, it is permissible for a woman to sit with her husband’s relatives, if she is wearing complete Shar`i Hijab. However, shaking hands with a non-Mahram man is prohibited.

It is not permissible for a man to kiss the mouth or hand or anything else of another man, or for a woman to kiss another woman, or to embrace or touch their bodies, etc., if that is done by way of desire. But if that is not done on the mouth, and it is done by way of respect and honouring, or to express emotion upon meeting and parting, then there is nothing wrong with it.