Cody Simpson's family have given his relationship with Miley Cyrus the seal of approval.

Cody Simpson

Cody Simpson

The 22-year-old singer struck up a romance with his old friend last month and his loved ones are thankful the 'Wrecking Ball' hitmaker makes him so happy.

Cody's sister Alli Simpson told Daily Mail Australia: "We love her. Cody is very happy and it seems that Miley is, too.

"We're always jumping on FaceTime with them. They always just seem so happy and I always say, if Cody is happy, we're happy. That's how we've always felt about our partners in life.

"If they're treating us well and we're treating them well, the family love it."

The 21-year-old singer-and-actress admitted she and her famous brother are comfortable talking about their personal lives because they understand curiosity from fans but try to find a balance and keep some matters private.

She said: "It's something you have to get used to, it just comes with it, we're doing this as a job, being in the entertainment industry.

"People want to know about it, all of us are happy to talk about it, but you also want to keep it somewhat private, that part of your life too, it's nice to live your best life with your partner and keep it private... we all just try and find balance with it."

The 'Pretty Brown Eyes' hitmaker recently gushed about how "happy" he and Miley - who split from husband Liam Hemsworth earlier this year - are together.

He said: "I'm very happy. We are very, very happy.

"She's creative. She's very passionate about what she does, and I'm very similar in that sense.

"That's why we get along so well.

"The reason why it hasn't been a really crazy sudden thing is just because we've been friends for so long."

He added that they "found each other again in a space where we're both not partying, working real hard, and it just keeps things healthy and it's good."

The blonde-haired hunk admitted their friendship has been "developing naturally into something more".

He continued: "Any girlfriends I've had in the past has always been immediate romance and so it's a different experience having been friends with somebody before and it developing naturally into something more.

"We just have a ball, yeah, and that's the most important part of a relationship, you know?"