Mehda and her sons Brijesh, Sanjay, Santosh and Vinod were sentenced to life imprisonment yesterday after they were found guilty of the crime.
On February 22, 2009, the woman along with her sons had set her daughter in-law on fire after her husband Dinesh had threatened to lodge a complaint against them over a property dispute.
The victim, Ram Devi was hospitalised where the magistrate recorded her statement before she died.
A case was registered in Chakairi police station against the mother in-law and her four sons.