Sir Paul McCartney delighted his fans when he shared a rare photo with his wife Nancy Shevell – and they look so in love!The Beatles star took to Instagram on Saturday to celebrate the couple's rescue dog, Rose, on Love Your Pet Day.MORE: Paul McCartney's epic £16.5million+ home is a tribute to The BeatlesIn the snap, Nancy affectionately rests her head on her husband's shoulder as they sit at the bottom of a staircase with their pooch in front of them.WATCH: Paul McCartney receives royal honour