Badar walked alongside the Queen's Press Secretary Ailsa Anderson to mount outside Buckingham Palace the official acknowledgement of the baby's arrival, the Daily Mail reported.
Dressed in the scarlet and black footman's outfit, Badar happened to be on duty at the Privy Purse door after the Duchess of Cambridge gave birth to the third in line to the throne.
Badar's father Mohammed Rahim, a 52-year-old welder, and his 41-year-old mother Mumtaz Begum still live in the same slum dwelling in Kolkata where Badar spent his childhood.
Badar's 20-year-old brother Mazhar spoke to him after his role in delivering the news of the royal birth.
"He acted very normal about it but it was a proud moment for him. My parents are so proud. They knew nothing about the British royal family before he got the job. They were really surprised. We did not know about any of it beforehand. We only read about it in the newspapers. My parents think Badar is blessed," Mazhar told the Daily Mail.
Their two-room home is shared between nine members of their extended family.
"I am feeling on top of the world," the footman's mother said.
"We were an economically challenged family," said Mazhar.
"Our parents let us boys sleep on the bed and they slept on the floor. But my father wanted us to go to a good school so that we could learn. He even borrowed money so that we could go forward."
Badar was taken in by the charitable St Mary's Orphanage and Day School run by the Congregation of Christian Brothers of Ireland.
The orphanage later sponsored Badar to go to the International Institute of Hotel Management College in Kolkata, where he took a degree in hospitality management.
After completing his first two years at the institute, the orphanage flew Badar to Scotland, where he completed his degree at Edinburgh's Napier University.
He graduated in June 2011 and landed a job as a junior footman at Buckingham Palace in February 2012.
"The conditions I live in now are so different from how I lived in India," Badar told the Daily Mail.