What is the ruling on kissing one's wife on the mouth in front of family and children?

The husband's action of doing that in front of family and children contradicts modesty (hayaa'), and modesty is part of faith. Therefore, he should not do it in front of his family, his wife's family, or his discerning children. If it is out of compassion and mercy, and the children are not discerning, then he should kiss somewhere other than the mouth.