Gomez's grandfather has confirmed she is secretly battling lupus.

The Come & Get It hitmaker was previously the subject of rumours she had the disease, and her family have now admitted she was diagnosed with the auto-immune condition "a couple of years ago" but has her symptoms under control.

Her grandfather Ricardo Gomez said: "She's in treatment. She's getting along pretty good."

Earlier this year, Gomez - who has an on/off relationship with Justin Bieber - checked into rehab and her elderly relative is desperate for her to now follow medical advice and take a break from her career.

He told RadarOnline.com: "We just saw in some newspaper that she was doing drugs. I called her and said, [you] need to watch out ... She was working a lot. She was exhausted. She hardly takes some time out. There was some pressure, first because it's a lot of work.

"The doctor was telling her she needs to take some time out It's just too much pressure what she's going through. It's just too much! She doesn't have a single day's break ... It's getting to the point with all this pressure ... that it's too much.

"Everyone was telling her, even her agent and the doctor, 'Selena take some time to yourself!' "

And Ricardo - who hasn't seen his granddaughter since last November - also claimed the former Disney star is keen to give up her pop career.

He added: "She was saying she don't want to sing no more, she just wants to be an actress ... but she's going to combine it, it looks like."