This is not an area I'm familiar with, so if any of the following description/discussion is misguided, I apologise in advance:
In languages with gendered nouns, the nouns for woman and man are normally feminine and masculine respectively. It's also usually the case that the grammatical gender of kinship terms reflects the sex of the individuals referred to. So mother, sister, grandmother and so forth will usually be feminine, and father, brother, grandfather will be masculine. This is sometimes referred to, I believe, as natural gender, where the grammatical gender happens to reflect biological gender in some way.
However, linguists are often at pains to point out that grammatical and biological gender are totally and utterly different things! This is clearly true. It would be unwise to suggest that French people conceptualised tables themselves as being female or having female attributes, even if the word table in French happens to be of feminine gender. Instead, it's probably better to think of grammatically gendered nouns within a given language as being grammatical classes/families of noun in the same kind of way that various European languages have -ar/ -ir and -er families of verb.
So my question is: are there languages which, for example, have (any, or a reasonable number of) grammatically masculine nouns for female kinship terms or grammatically feminine nouns for male kinship terms?
Also of interest would be languages with a grammatically feminine word for boy or grammatically masculine word for girl or similar.
In other words are there languages where the grammatical gender occasionally or often does not reflect natural gender?