A couple is suing their son and daughter-in-law for $650,000 for not giving them a grandchild

• Sanjeev and Sadhana Prasad are suing their son and his wife for $650,000.

• The Prasads say their son inflicted "mental cruelty" on them by not producing a grandchild.

• They are requesting the sum if the couple does not have a child in the next year.

A couple in India are taking legal action against their son and his wife, accusing the younger couple of inflicting "mental cruelty" on them by not producing a grandchild.

Sanjeev Prasad, 61, and his wife Sadhana, 57, say their son, Shrey Sagar, and his wife, Shubhangi Sinha, should pay them $650,000 if the couple does not give them a grandchild within a year, according to the BBC.

The older couple, who live in the northern Indian state of Uttarakhand, told the Times of India that the sum is what they spent on Shrey, who is now 35. This includes a $65,000 bill for Shrey's pilot training in the US in 2006 and a luxury car gifted to him for his wedding.

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"I have only one son. I spent all my savings on his upbringing and education," Sanjeev Prasad told the Times of India. "He returned to India in 2007 due to the economic recession abroad. He had lost his job and could not find another for over two years. I supported him financially during this period as well."