It is conceivable, but illegal in most jurisdictions. This would be considered incest.
Your grandmother's sister's grandson is your second cousin.
In India, as per the Hindu Succession Act, a grandson has rights to his grandmother's property only if his parent who is the deceased's child is also deceased. The property will be divided among all legal heirs as per the law, which may include the grandson depending on the circumstances. It is advisable to seek legal counsel to understand the specific details of the situation.
Your grandmother's first cousin's grandson is your third cousin.
Your grandmother's sister's daughter's grandson is your second cousin, once removed.
Your great grandmother's brother's great grandson is your third cousin.
Your grandmother's sister is your great aunt.
The son of your grandson is your great grandson. You are his great grandmother or great grandfather.
Your great grandmother's first cousin's grandson is your third cousin once removed
Your great-grandmother's first cousin's grandson is your third cousin once removed.
Your grandmother's grandson is you, your brother or your first cousin. So your grandmother's grandson's daughter is your daughter, your niece, or your first cousin, once removed. You are her mother or father, her aunt or uncle, or her first cousin, once removed.
The grandson of your great grandmother's brother is second cousin to one of your parents, and your second cousin once removed.
There is no relation between you and your grandmother's cousin-in-law's grandson.