Kylie Minogue's family fear the singer is struggling with the chemotherapy treatment she is undergoing in a bid to beat breast cancer.

The Aussie star's uncle insists the therapy is having a positive effect - but her loved ones are concerned she may not be strong enough to handle the harsh anti-cancer treatment.

Minogue's uncle DENNIS RIDDIFORD says, "The chemotherapy seems to be working - she is halfway through her treatment and has a couple of months left.

"But still it won't be over - you never ever know when it might come back.

"Obviously, it's a worry she might not make it. She's such a tiny little thing - she has been struggling to cope with the treatment.

"It has been wearing her out. I know it has made her very weak."