Bangalore, Dec. 30: Carmine Mathias, 93, always knew that the child she had cared for decades ago would turn up at her door one day. When the child, now foreign minister of Bahrain, came calling this week, she shed tears of joy.

Shaikh Khalid bin Ahmed bin Mohammed al Khalifa, 56, a member of the Arabian country's royal family, turned up with his wife at a modest Mangalore home on Wednesday and Thursday to meet his former nanny during a private visit to India.

Carmine had spent 50 years at one of Bahrain's royal palaces bringing up the four children of Shaikh Khalid's father, who then headed the oil-rich country's police department, and later his grandchildren.

Her family had been told about the impending visit a few days ago. They were thrilled when the royal couple, who had checked into a hotel, arrived at their one-storey home in a rented car without fanfare or security.

"The Shaikh and madam (his wife) walked in like commoners. I was stunned," Carmine's grandson Francis Monteiro told The Telegraph today. "My grandma insists she always knew the Shaikh would visit her, but says she is very happy."

Carmine wasn't feeling well enough to take phone calls today.

Although the royals had kept the visit private, the news went viral after Shaikh Khalid tweeted his picture with Carmine.

"With my nanny who looked after me as her son since my childhood. Mama Carmine Mathias, at her home in Manglore (sic), Karnataka," a brief note attached with the picture said.

"She came to Bahrain when she was 35 years old in January 1959. Now she is 93. She looked after my late brother Abdalla, myself and my two younger sisters Maie and Lulwa. She gave us the best of her love and care.. we cherish every moment in our life with her."

Monteiro, forensic expert and principal of the AJ Institute of Allied Health Sciences in Mangalore, 340km from here, said the Shaikh and his family phoned Carmine "at least once a month to check on her well-being".

Carmine had visited the Bahrain royals several times after her retirement in 2009.

"She last visited the royal family for a month in 2015, after a six-month stay in 2012. They invite her for all events (such as weddings) in the family," Monteiro said.

Shaikh Khalid wasn't the first royal to visit Carmine's home in Bajpe, near the Mangalore International Airport. His parents and two sisters had come in 1987 while Carmine was vacationing at home.

Monteiro said the parents had put up at Carmine's home for a couple of days while the two sisters spent a week there. "I was a kid in 1987 but this time I really got to see the royal family's simplicity," he said.

Carmine's nephew Salvador recalled Shaikh Khalid twice taking his aunt to Rome on pilgrimage when she served the family.

"He also took her to Britain and America when he was Bahrain's ambassador to these countries," Salvador said.

On Tuesday, the Shaikh and his wife had visited Layla, a former "helper" of their family, at Kollam in Kerala. They left for Mumbai this morning.