Palak Singh 03 April 2020
Hello, answering to your question that "Whether I can marry my father's sister's grand-daughter?'
There are few relationships under which a Hindu marriage can never be solemnized. This domain of relationship is known as “degrees of prohibited relationship.
The Hindu Marriage Act, 1955 has clearly mentioned the Sapinda relationship. As per Section 3 of The Hindu Marriage Act, 1955, it is understood that Sapinda relationship with reference to any person extends as far as the third generation (inclusive of his present generation as first generation) in the line of ascent through the mother, and the fifth generation (inclusive of his present generation as first generation) in the line of ascent through the father, the line being traced upwards in each case from the person concerned.
It means that while upward tracing of line of ascent either through mother side or father side if they converge at the same person after 3 or 5 generations then such relationship is termed as Sapinda relationship.
In your case, your father’s sister’s granddaughter comes within prohibited degrees of relationship, hence you cannot marry her.
In Shakuntala Devi vs Amar Nath [AIR 1982 P H 221], Punjab and Haryana High Court held that two persons can marry within the prohibited relationship but there should be a proof of established custom i.e. very old and beyond human memory. But in Balusami Reddiar vs Balakrishna Reddiar [AIR 1957 Mad 97], it was held that the custom must not be against public policy and morality. Hence if you can prove that it is an old custom that is followed in your community then it MIGHT be acceptable, but it mostly isn’t.
Hope this answers your question!