Cristiano Ronaldo's son is asking questions about his biological mother

In her latest autobiography, Cristiano Ronaldo's mother Dolores has admitted that the superstar's son still does not know who his biological mother is.

The boy, affectionately called Cristianinho, is the love child of Ronaldo and an unidentified woman he met in a restaurant on holiday, whom he found attractive. The woman was believed to be a surrogate.

Dolores, who looks after her grandson - born in 2010 - at their family home in Madrid, said the four-year-old has asked after the whereabouts of his biological mother. However, Dolores maintains in the book that her identity "will never be known."

Ronaldo's sister Elma added: "Once we told him she was in Heaven, but my brother and mum asked us not to repeat it. We say now his mum went traveling. He goes silent, forgets about at and doesn't ask anymore."

She said: "If later on Cristianinho wants to know who his biological mum is, it will be his decision and no one’s going to stop it."

Meanwhile, Ronaldo himself has been enjoying his summer holidays in Greece with girlfriend Irina Shayk, after a disappointing World Cup with Portugal which saw them crash out in the first round.

Sports Illustrated model Shayk, 28, who also appears in the new Hercules film with Hollywood star Dwayne "The Rock" Johnson, has been spending quality time with her beau after choosing to skip out on joining the tournament 'WAGS' in Brazil.

The couple, who have been dating since 2011, are clearly having a laidback time, with Real Madrid forward Ronaldo posting this Instagram photo of him in a facial mask.

In other news, Germany's World Cup winning goalkeeper Manuel Neuer has also been making the most of his pre-season by holidaying with girlfriend Kathrin Gilch.

The 28-year-old Bayern Munich star, widely regarded as the best custodian in the world, was pictured with his other half and friends while on vacation on Mykonos Island.

Neuer took time out to take photos with fans as they spotted the star and stopped him for a chat.

Gilch, who met Neuer on a plane while on holiday, has been dating the goalie for five years and according to German media, the couple are now looking at purchasing a cozy home in the Bavarian town of Tegernsee.

After his deserved break, Neuer will travel with the rest of the Bayern squad to New York for their summer tour. The German champions won a domestic double last season in coach Pep Guardiola’s maiden campaign in charge.

Pep will be wondering just how this upcoming season can topple the last couple of years after such dominant local and global success.