Dear Christopher,

It's true that Turkish inheritance law involves an institute named "reserved portion" as the testators are merely allowed to dispose the inheritance rights of their successors within the proportions/percentages stated in Turkish civil code, whist the British testators are utterly free on disposing their assets regarding inheritance issues in British law. However, Turkish civil code was amended as abrogating the article of the siblings' reserved portion on the 10/05/2007.

In light of the foregoing, your wife(RIP)'s brother may either be a sucessor of her assets with reserved portion, or not as depending on the death date of your wife.

On the assumption that your wife passed away before the date 10th May 2007, you and her brother will acquire her assets on a 50/50 basis. The reserved portion of a sibling was 1/8 in the ex arrangement of the Code, thus he will have the 1/8 of his 50% portion in any case even if there's a valid testament left by your wife as devesting her brother's inheritance rights.

In the second assumption(your wife passed away after the new legal regulation had come into effect), her brother will be able to get totally devested of his inheritance rights provided that there's a valid testament left from your wife for this purpose.

I've tried to summarize everything you need regarding the reserved portion issue of a sibling under Turkish inheritance law shortly. If there's still a point unclear in your mind, please don't hesitate to ask anything you'd need to know.

Best wishes