A surrogate mother has given birth to a baby boy – four years after his parents were killed in a car crash.

The fertilised embryo was implanted in the woman from Laos, following a protracted legal battle by the parents of the Chinese crash victims.

The baby was born in December, though news of his birth was only reported by The Beijing News this week.

The little boy – named Tiantian – which means sweetness – is the biological child of Shen Jie and Liu Xi, a couple from Yixing, East China’s Jiangsu province, who died in an accident in March 2013.

Shen and Liu, both only children, had been having fertility treatment at the time of their deaths, and their families were eventually granted the frozen embryos.

Because surrogacy is banned in China, a 27-year-old surrogate mother was sourced in Laos, though she travelled to China on a tourist visa to give birth, the Straits Times writes. Seeking surrogacy overseas itself is not illegal. 

In quotes reported by the South China Morning Press, the child’s maternal grandmother said: “He’s always smiling. His eyes are like my daughter, but he looks more like his dad overall.”

The boy’s paternal grandfather says they will initially tell the child his parents are overseas, but when he is old enough they will tell him the full story of his birth.