Kate's message to Brad?

She’s determined to keep people guessing when it comes to her rumoured romance with Brad Pitt.

And now Kate Hudson has fuelled the fire once more by sharing a Valentine’s Day video of her belting out a version of Rihanna’s Love On The Brain to a mystery someone.

“We got love on the brain and sending you all ❤'s! Happy Valentine's Day from our fam to yours,” Kate captioned the mesmerising video.

The Almost Famous actress’ son Ryder, 13, also appears in the video, clinging on to the top of the yellow velvet couch like a sloth as his mum sings her heart out.

Mid-song, Ryder then adorably cues his mum to make a heart shape with her hands.

Rumours romantically linking the pair have been swirling since the Golden Globes earlier this year.

The blonde beauty was reportedly overheard confirming their fling to friends at two Golden Globes afterparties, with Woman's Day magazine claiming she told one group they'd rendezvoused on "several occasions" since his split from Angelina Jolie.

And despite not making an appearance together, the pair may have managed to squeeze in some private time, with the mag reporting that Kate, 37, was spotted having an "intimate" conversation with Brad's agent, Bryan Lourde, before being spirited away from the party in a car that had the exact same number plate as the one that Brad left the earlier ceremony in.

In November last year a former bodyguard of Brad's hinted that the pair had been hooking up since the Allied star's marriage to Ange ended last September.

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“They make a great celebrity couple. It wouldn’t surprise me at all if they were dating," Kris Herzog told Woman's Day magazine.

An inside source also seemed to confirm Kris' theory of the new Hollywood romance adding, "Kate is Brad's mystery woman. They've been extremely close over the past few weeks, following several secret meet-ups."

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