Like what I read here about the Hindu family indications, the africans have the same almost incomprehensible mix up of cousins beeing called brothers and brother's son's beeing called also son by the uncles and aunts, but I've really given up on figuring that out. I gave up hope on that completely and think it's allright as long as they themselves can follow it.
But for us, could you not do a little improving? Making a female cousin : cousina ( and for Dutch it'll be harder work to put it right) . But this is about English so first things first.
It sounds good enough cousina,no? Or would it be too easily confused with casino?