We have dual French and British nationality and are resident in France. As we have no children, we wish to leave our house and the rest of our possessions to our British nephews and nieces in the UK, but apparently we need to prove that they are directly related. As the livret de famille does not exist in the UK, how can we prove that they are directly related to myself or to my husband? The proof appears to be a requirement for our French wills. A.S.