Katy Perry's in the pink with Russell's mum

The songbird invited hubby Russell's mum to watch Ghost: The Musical in London last night.

Dressed in candyfloss colours, the chart-topper linked arms with the more soberly-attired Brand.

Her husband meanwhile remained across the Atlantic.

Yesterday he was spotted mucking about with a couple of his friend's tots on a day out in LA.

And on Saturday he performed in Canada a fortnight after having been refused entry because of visa issues.

Katy is currently in the middle of a sold-out UK tour.

She played London's O2 Arena on Friday and Saturday.

She plays Liverpool tonight, before more stops in Cardiff, Belfast, Birmingham, Newcastle and Aberdeen.

Theatre visit ... Katy Perry and Barbara Brand

And she has revealed she has been "going off like a firework" thanks to her love of baked beans.

The singer admitted she's been having flatulent repercussions from the canned favourite.

She said: "I love coming to London so I can have baked beans on toast. They do bloat me and I'm afraid I'm going to go off like a firework, but I do love them."

The 26-year-old proved how much she enjoys them by buying TWENTY tins.

Within hours of arriving in the country, the star made a special visit to Harrods food hall in Knightsbridge, West London, to stock up.