Cullum: 'Dahl was out of my league'
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The couple began dating in 2007 and married three years later (10) before welcoming a baby daughter last March (11).
Cullum admits he thought the model was out of his league when they first met and was stunned when they discovered a mutual attraction.
Speaking on Britain's Radio 4, he says, "We started chatting about books we both loved and she was a proper bookworm and we just got on really well.
"I didn't entertain for one second that she would be interested in me. I assumed that everyone who met her would fall in love with her so I didn't necessarily think it would be my place, so I played it pretty cool.
"She was living in New York and she had a boyfriend. Six to eight months later she moved back to England and obviously it became more after that."
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