Justin Bieber duets with half-sister Jazmyn at Toronto’s Massey Hall

Baby, baby, baby, aww! Pop star Justin Bieber gave his Toronto audience a dose of the cutes Wednesday night when he sang a duet with his four-year-old half-sister, Jazmyn.

The "Baby" singer brought "Jazzy" on stage during his acoustic Christmas performance at Toronto's Massey Hall for the "Justin Bieber Home For The Holidays" Christmas special, which aired on MuchMusic last night.

"Jazzy!" Bieber called out as the four-year-old appeared on stage and jumped into her half-brother's arms.

"Princess Jazmyn," who sported a 'do not unlike the Biebz' famous swish, was clad all in pink and kneeled in her big brother's lap to sing with him a very high-pitched, off-tune version of his hit song "Baby." And you have to hand it to the girl: she knew all the words!

"Give it up for Jazzy, everyone," Bieber called out to the crowd before revealing that the pre-schooler had shaved her little brother Jackson's head for the holidays. The sibs proceeded to sing part of "One Time" before Jamzyn returned to her dad.

Bieber was a big hit with the kids Wednesday night. Not only did he duet with his younger sister, but he also handed over a $500,000 cheque to the Children's Wish Foundation.