Is it permissible for Muslim lawyer to write a will for a non-Muslim client in accordance with the English law since the non-Muslim may have bequeathed some or all of his wealth to such institutions which may either be unknown or even prohibited like the institutions for caring of dogs or sailors?

There are some illnesses which inflict people and which they ascribe to the Jinn. There are also people who claim to see and hear the Jinn, and to command them and carry out many actions through controlling them, or through their controlling people. What is the reality of this? Is there any material, sensorially-perceivable relationship between man and Jinn?