Justin Bieber has posted pics of himself and his wife, Hailey, getting cosy together on his 31st birthday.

The Peaches singer took to Instagram to share behind-the-scene photos from a cabin getaway with his wife and friends for his birthday.

The snaps showed the couple singing, cuddling and holding their six-month-old son, Jack.

Bieber didn't caption his photo dump, but his businesswoman spouse commented with a series of heart emojis.

The duo appeared in good spirits during their getaway after the Baby singer's rep was forced to deny allegations that he was struggling, following concerns about his recent erratic behaviour.

The spokesperson told TMZ last week that the allegations behind Justin's mental and physical health were "exhausting and pitiful" and the opposite of "the obvious truth".

"People are committed to keeping negative, salacious, harmful narratives alive," his rep stated.

The rep also defended the pop star's New York City outing last month when he stepped out looking bleary-eyed and exhausted.

According to his spokesperson, the Stay singer was taking care of his son and working late in the recording studio on a forthcoming project the night before.

Bieber has since been making fun of the drug-use rumours by rapping about being high and smoking in videos shared to Instagram.