Facebook status change gave him the right answer!
The venue: The couple married on August 4 in a ceremony at St John's Church, Canton, Cardiff, followed by a reception and party at Cardiff Castle.
How they met: Sin and Matthew first met in 2008 while both working at Tesco in Canton, but only got together as a couple the following year.
Matthew was working as the store manager and Sin worked as a customer assistant while studying criminology and criminal justice with sociology at the University of Glamorgan.
Sin said: "I thought he was funny and I thought he was cheeky - and that's what I like.
"We were just friends at first and then we just started texting each other. We met up a few times and it just happened from there."
The proposal: Matthew popped the question in June 2010 at the home of Sin's mum, 50-year-old Dawn, in Ely, Cardiff.
Matthew told Sin he was going to buy a necklace for his mum's birthday, but returned later with a large 18-carat, white-gold engagement ring.
But Sin kept Cardiff City fan Matthew waiting for an answer, telling him she would "think about it".
She eventually informed Matthew of her decision - by changing her status from "in a relationship" to "engaged" on Facebook.
Sin's virtual answer to Matthew's big question echoed how the couple first became an item.
She said: "That's how we did it when we got together - I just said we're in a relationship on Facebook."
The wedding: Sin travelled to the church ceremony using a horse and carriage, while her mum, nan and bridesmaids hopped in a white limousine.
Sin walked up the aisle to Canon in D. She said: "I was nervous at first, but once I was up where Matthew was, I was fine and just enjoyed it."
After the ceremony, the couple travelled to Cardiff Castle using their horse and carriage.
Sin said: "We had a lot of tourists taking pictures of us from all over the world."
The newlyweds' wedding cake was sculpted into a purple and gold princess castle, with daffodils and Cardiff City flags at the top.
It was made by The Cake Makers in Canton. Sin said: "They did a fabulous job. We were really pleased with it and it was a talking point of the wedding. Everyone was really impressed with it."
The guests were entertained into the night with a disco, and the couple's first dance was to Elbow's One Day Like This.
The newlyweds honeymooned in Florida for three weeks.
Sin and Matthew thanked their parents for their "love and support".
Summing up her wedding experience, Sin said: "It was stressful at first, but well worth it."
* Sin Reed and Matthew Stephens, who married at St John's Church, Canton, Cardiff, with some of their friends at Cardiff Castle PICTURE: Andrew Davis Photography www.andrew-davis-photography.com