Is it permissible for a young Muslim woman to kiss her young brother, maternal uncle, or paternal uncle in public, in front of passersby, under the pretext of greeting?

It is permissible for a sister to kiss her brother or one of her mahrams upon his return from travel, provided there is no fear of fitnah (temptation) or suspicion. However, the kissing should not be on the mouth, but rather on the forehead or the head. It should also preferably not be in the presence of non-mahrams. If the husband forbids his wife from kissing her mahrams, she must obey him.