Adele's half-brother has revealed his relationship with the singer is "hard", because her superstar lifestyle means she's too busy to speak to him.

Cameron O'Sullivan and sister Adele have the same father, Mark Evans. But while the Grammy-winning singer wows crowds across the globe, 20-year-old sports medicine student Cameron has quite a different existence in a small terraced house in Llantwit, South Wales, which he shares with his mother.

In a new interview, Adele's rugby-loving younger brother has spoken out for the first time about his upset at not getting the chance to see his sibling enough, due to her busy performance schedule.

Speaking to Britain's The Sun newspaper on Monday (21Feb16), Cameron said: "It’s hard because we never see each other. We’re not close at all and that’s the most difficult thing.

“I’m really close with her mum Penny (Adkins), but that’s it. I keep in contact with Penny on the phone. But I hardly speak to Adele. There’s nothing there. She’s so busy we’re not really close. I’ve not spoken to her for a while.”

Adele, 27, has rarely mentioned her brother and the pair grew up in different homes and first met in 2007. Speaking in 2011 she admitted, “He looks like my twin - same hair and everything.

“It’s bizarre growing up in a completely different city but then, when you see each other, it’s as if you’ve spent every day of your lives together.”

Cameron is hoping that if engagement rumours surrounding Adele and her partner Simon Konecki are true, he'll get an invite to the wedding. He also admits that he hasn't seen his nephew, Adele's three-year-old son Angelo, since he was born in 2012.

Both Adele and her half-brother are rumoured to be estranged from their father Mark, after he walked out when the singer was two. Cameron admitted that his own relationship with his father "just fizzled out."

Meanwhile, Adele hit headlines after revealing to fans at London's O2 Arena on Sunday (20Mar16) she won't be attending Rihanna's London Wembley concert this summer in case she passively inhales marijuana.

The outspoken singer claimed she would be avoiding the gig because the smoke might affect her voice and get her "stoned" the day before she's set to headline the Pyramid Stage at English music festival Glastonbury on 25 June (16).

The singer is billed to headline the Saturday night slot at the five-night music festival, which will also see Muse playing on the Friday night and Coldplay closing the event with a penultimate gig on the Sunday (26Jun16).