Hey, Courteney. Whatcha got on yer ring finger there? You didn't wear it on Letterman on Monday... Or while you were wandering around the Tribeca Film Festival last night... Why are you only wearing it in a car park?!

Monica, who started dating Snow Patrol's McDaid in September, was spotted wearing a rather sizable diamond ring on her ring finger as she strolled through Los Angeles International Airport (LAX)  on Sunday.

A source told Us Weekly magazine that their wedding will be "sooner than later" and "they are talking about having a child together."

The 37-year-old Northern Irish singer's mate Ed Sheeran recently predicted that the couple, who moved in together last month in LA, would tie the knot in the future.

He said: 'I wouldn't be surprised, but it's still early days. They certainly enjoy each other's company and feel very comfortable with each other... I'm not sure that it's public knowledge, so maybe I shouldn't have said anything - but, yes, they're already living together. Things are moving fast. He moved in and, judging by the last time I saw them, they couldn't be happier."

An ever present 'insider' added: "What has really impressed Courteney is how good Johnny is with Coco. She didn't let any other men near her daughter but he's always out in their grounds playing sport with Coco and bonding with her. Also, David (Arquette) approves of him - they've met a few times and are even planning a dinner with David and his partner Christina. They're all comfortable around each other. Johnny doesn't feel at all awkward about it."