Is the disabled brother obligated to pray and fulfill religious duties, and is he entitled to a share of the inheritance, especially since he refuses to learn Al-Fatiha and prayer due to difficulty in pronunciation?

The religious obligation of a disabled brother, such as prayer, is based on the presence of his intellect. If the disability affects his intellect and he loses discernment, then nothing is incumbent upon him. However, if he is of sound mind, then he is obligated.

If he is obligated, the disability waives some of the duties he is unable to perform, such as praying standing, so he prays sitting; or reciting the entire Fatiha, so he recites what he can. This is based on the principle "what is feasible is not waived by what is difficult," and the principle "whoever is able to perform part of an act of worship must perform that part."

The brother should be taught Al-Fatiha and prayer gently, and he should perform what he can. His inability to pronounce some letters or his mixing of them does not harm him, and his prayer is valid.

As for inheritance, he receives his full share; for physical and mental soundness is not a condition for entitlement to inheritance.