Jeremy cycles seven miles to work and frets about the mortgage on their Canonbury fixer-upper.

Ursula loves health food shops and anything ‘chemical free’, wilfully unaware that a chemical is, quite literally, any substance.

A long-suffering doctor once tried to explain that chemicals do not, actually, have a morality. He gently told her that even pure mountain water, just like the Voss she was clutching, is a chemical. But Ursula feels reassured by the nice, natural sounding words all the same, and pictures of trees on Wholefoods labels make her feel like she’s doing her bit.

Wringing her hands, she turns casual kitchen suppers into environmental symposiums. Volunteering to help, she arrives early with home-made hummus and chases her host around with separate bags for compostable waste and recyclables.

A rogue tangerine peel tossed in the bin is promptly dug out and flung on the fire. Smiling beatifically she announces that she’s (three weeks) pregnant with Ilya, an Indigo Child who’s to be home-schooled and, she hopes, may one day stand as Islington North’s MP. She bristles at anyone who tops up her glass.

She hopes the news of Ilya’s arrival won’t outshine her Greenpeace news. She chairs Planet Hearth, the local action group for climate change and takes her role as seriously as that of a Pentagon agent guarding nuclear codes. Ursula wholeheartedly believes that all it takes is a few more signatures to change our children’s future.

Jeremy writes passive aggressive letters about their Tory MP to The Guardian comment pages but is yet to be published. He prepares industrial-sized batches of lentil bake each Sunday, but for all Ursula packs and freezes Tupperware she’s not had the heart to tell him she’s intolerant to pulses.

Ursula feels most at home with Corbyn, the rescue tabby, and secretly wonders if there’s actually any point in having a baby. She feels guilty about the additional carbon footprint and wonders, really, where she’ll find the time alongside all her campaigning and youth work.

In quiet moments, Jeremy wonders if they have to live quite so relentlessly as eco-worriers. When Ursula leaves for her dawn swim on the Heath, he, very occasionally, sneaks out to Starbucks for a frappuccino.

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