The deceased couple was undergoing fertility treatments before the fatal accident in 2013.
Their parents fought a drawn-out legal battle to gain access to the couple's fertilised embryos, kept in a hospital in the eastern city of Nanjing.
Surrogacy is illegal in China, forcing those who can afford it to look for potential options abroad.
Laos has become the latest impoverished nation in Asia to witness a flourishing but legally opaque commercial surrogacy industry after countries like Thailand, Cambodia and Nepal outlawed the practice in recent years.
"He's always smiling. His eyes are like my daughter's, but he looks more like his dad," new grandmother Hu Xingxian, told the state-run newspaper.
The grandparents had to clear several hurdles to transport the embryos out of China and prove the paternity and nationality of the baby once it was born.
"First we thought of using air freight, but none of the airlines were willing to take the thermos-sized bottle of liquid nitrogen where the four embryos were stored," Liu Baojun, a surrogacy expert who assisted the families, told The Beijing News.
So the families decided to transport their precious cargo by road to Laos, where commercial surrogacy is legal.
The child was kept in the hospital for 15 days, until all four grandparents gave blood and DNA tests, establishing the baby was indeed their grandson and that both parents were Chinese nationals.
The landmark ruling that allows parents to inherit frozen embryos created by their children has triggered a wide-ranging debate on Chinese social media.
Dozens of commentators said it highlights the plight of parents who have lost their only child under China's controversial one-child policy. Others discussed the need to legalise surrogacy.
"This is a family that is rich and capable. But, there are many others that have lost their only child. Shouldn't the government offer them any support (for the price they've had to pay) for complying with family planning policies?" asked one commentator on Twitter-like microblog Weibo.
The three-decade-long restriction on family size was replaced by a two-child-rule in 2016.
Tiantian's grandfather Shen Xinnan told The Beijing News that he will wait until the boy is "older and wiser" before telling him what happened to his parents . "In the meantime we will say his mum and dad are living abroad," Shen said.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)