Robin and Cat Lang’s eight-week-old daughter, asleep in her father’s arms, has a middle name they picked out when they had only been going out for a couple of months – 15 years ago. The couple recently re-read the teenage emails they had written to each other, talking about how they would get married and what they would call their children. “We were a bit ridiculous,” says Cat, laughing. “We were saying ‘I love you’ after a week.”

They met, aged 11, in the same form at their Harrogate secondary school. “We were both quite geeky but he was in the boy geek group and I was in the girl geek group,” says Cat. “They were always there in the corner, or in the library. We would be in our corner, or in the library.” Did Robin notice the girls? “We were mostly intimidated by them,” he says.

The following year, they sat together in maths, bonded by a dislike of their teacher and a liking for Philip Pullman’s His Dark Materials trilogy; in year 11, aged 15, they became good friends, “when we formed,” says Robin, “more of a joint boy and girl friendship group, around politics and history.” “It was very geeky,” says Cat. “We got into politics; we were staunchly socialist – quite extreme back then – just discovering communism and ideas like that for the first time. One of our friends set up an online forum and we were all members, so we would talk on that when we were allowed to get on to the dial-up internet at home. I liked Robin’s posts – they were funny, and I agreed with the same sort of political ideas. It made me think about him a bit more.”

‘Being together and talking and talking’ … Robin and Cat Lang as teenagers.

They held what Cat calls, mock-earnestly, a “political gathering” at her house while her parents were away. “But of course we were teenagers, so there was beer,” she says. “It didn’t stay very highbrow.” The friends kissed – a surprise to both of them. Didn’t they fancy each other? “I did but I didn’t feel like it was a realistic prospect at the time,” says Robin. “It didn’t feel like something I would be able to pluck up the courage for in a normal situation.”

Cat’s happiest memory of that time is of “just being together and talking and talking”. “There was lots of walking around the park in the rain and wind,” says Robin. Did they think they would be together for ever? They both laugh and say yes. “We were friends and we became best friends,” says Cat. “Robin made me really happy. We were well suited and lucky.”

Their families thought it would probably be a short-lived teen romance, but after Cat spent a year in Sweden during her degree, they got engaged and eloped to Gretna Green to be married at 20. “I wouldn’t say monogamy is for everybody; that everybody should get married at 20. For us it was right,” says Cat.

They must have changed since they were 16 – how have they navigated that? “It’s more that we’ve changed together and changed each other,” says Robin. “We have changed but in ways that make us fit together more rather than diverge.” Cat agrees (they seem to agree a lot). “We started our careers in teaching together, we became parents together. We’ve helped each other through any times that have been stressful or hard, and generally shared in the same experiences.”

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