Visa for Mother of 4 British child.

[rajajin]

Hi
My Mother-in-Law age 45,is Pakistani citizen and married to a British citizen who died in 2010.Her husband lived in Pakistan with her from 1988 to 2001 around 13 years and got 4 children which all are British Citizen.
She applied spouse visa 3 times which unfortunately rejected every time between 2002-2007.
Is there anyway she can come over here in UK to live with his 4 childrens (All of them are over 21 and British by Birth).
Mother and Father (both deceased) of my Mother-in-Law were Registered British subjects but they never claim any sort of British citizenship or British passport and my Mother-in-Law never registered as daughter of Subjects.
Any kind of Visa she can apply???

[Wanderer]

Almost zero, there's the ADR visa, costs a lot and very difficult to get, need to be able to show incapacity etc....