LONDON - Victoria Beckham is “sick with worry” over fears that her younger sister, Louise, may be suffering from a brain tumour.

However, her friends say that she is determined to put on a brave face for the sake of her three sons.

It was when Louise, who is also a mother of three, was hit by a series of crippling migraines that the family started worrying about her health.

Family friends have revealed that the 32-year-old collapsed in agony at her parents’ home, and, as the intensity of the headaches grew, doctors sent Louise for a battery of tests, including an MRI scan.

That sparked fears among family and friends that Louise, who divorced from her husband- mobile phone company boss Hayden Isted, 34-two years ago, might be suffering from a brain tumour.

But Louise told her family - including Victoria, 35 - to “carry on as normal” and not to worry as she was convinced everything would turn out to be fine.

“Victoria was worried sick. Louise is not just her kid sister but also her best friend. It’s been hard for Victoria but she’s had to carry on for the sake of her boys,” the Daily Star quoted a source as saying.

“She also didn’t want her own fears to overshadow Romeo’s seventh birthday.

“Victoria has been putting on a brave face, but there have been a couple of occasions when the emotion has got to her and her mask has slipped,” added the source.

However, Louise’s tests are said to have revealed that she is not suffering from a brain tumour.

“Thankfully Louise is not seriously ill - but she has been suffering from some bad migraines,” said a family friend.

A spokesman for Posh said: “Health is a private matter and we never comment on private matters.” (ANI)