Canadian sensation Justin Bieber is enjoying some "family time" away from his busy schedule.

The international superstar took to Twitter last night (May 30) to reveal he was celebrating his younger sister Jazmyn's birthday with his loved ones.

Bieber, 19, is currently on a month-long break from his gruelling 'Believe' tour, and is seemingly making the most of his time off with family members.

Taking to the social networking site, the singer wrote: “HAPPY BIRTHDAY @JazmynBieber !!! I love you! #HappyBirthdayJazzy (sic)," before later adding: “#familytime #HappyBirthdayJAZZY.”

Bieber also made fun of his little sister as he posted a photo of her lying on the sofa on his Instagram page, with the caption: "the birthday girl is tired (sic)."

Jazmyn and her brother Jaxson are Bieber’s half siblings from his father Jeremy’s marriage and the star has been spotted with them on numerous occasions.

Bieber's parents Patti and Jeremy have both been supportive of his hugely successful career, and the star has previously gushed about his strong family network.

He said: “My parents weren’t the type to talk trash about each other.Some parents, when they split up, the mom will say, ‘Your dad’s a jerk,’ but mine were never like that. So that definitely made it easier for me. I knew they loved me, and they split up because of them, not because of me.” Watch Bieber's video with will.i.am here: