Where did she lived in India (Are you sure it was India?) Where Her husband died? Where their childrens are born?
Have you precise date for their wedding? For her husband's death, For the birth of the childs?
What else do you know about your father's uncle? Was he a Stocklin or a Hoogstraten?
Where did you found Marie Helene birth date? How did you found she was born in Alsace, not in Doubs?