Hi,

You and your brother are your uncles beneficiary. You can make a will in Turkish Law. But you can't touch your beneficiaries legal rights which is settled by law. In that case you and your brother are his beneficiary. If he didn't make a will you will get all his properties,money and shares. How will you find them? and make a list about .This will be next question.I hope he makes will and make a list about his belongies. Deed Office is very good for registration in Turkey, Also National Register office using net system. If you know your uncles register detail you may find his id register details. If there is a adopted child. By the way you didn't tell us your grandparents sitiuation. Are they living? If they are alive inheritence sharing table will change.

I hope its help you.

Cheers