Buying joint property.

When Mother of A witness to the will during his lifetime she obivously must have consented it, then she lost her rights unless the Will is genuine produced by his wife who married thereafter his death. Again, the question arise, whether she marries before parting the property or after parting of the will property? if, she has married the second husband after obtaining the will property then the said property is her self aquired and what does she feel she can dispose off. 

As far as concern the registry of the documents without demarcation is not a ground and same may be done at later stages. The registry authority is precluded with the portion of demarcated by concern only about her portion of the property and registered the same.

Will was in the name of his brother not wife.

Such being the case, the first wife lost her rights to claims, unless the will was made in her favor for settlment of his dues or seperations. If, she has seperated during his life time automatically, her marriage with first husband is disolved and the will made by the person in favor of her brother which shall be more effective.