Ruth Linton, my mum, is an eternally overdressed, perennially late, sixtysomething (don’t ask, because she’ll always deduct two years), divorced, Jewish grandmother. She is also, it turns out, an aspiring standup comedian.

Her smile is the first thing people notice. But, behind it, confidence used to elude her. Then, in August 2014, she was diagnosed with a meningioma (a slow-growing tumour that can go undetected for decades), at the same time as dealing with the loss of both her parents and the breakdown of her marriage, to my dad.

She was admitted to hospital, placed on a huge dose of steroids to stem the tumour that had caused months of crushing headaches, and then operated on 48 hours later. “I woke up from the op in floods of tears,” Mum reflects, five years on. “It lasted a couple of hours, and from then on everything was hilarious to me.”

The steroids triggered a major chemical imbalance. Mum spent more than a month in hospital, displaying behaviour so out of character – such as whispering to a crucifix in the Christian chapel, and casting a film of her life – that it was excruciating for my brother and me to watch. It turned out that this was also her comedic awakening. “I can only think that it was a coping mechanism. The shock of going from normality to near death was too much to process,” she says. Visiting Mum when her behaviour bore no resemblance to the parent I knew was frightening, but what followed was worse. Discharged from hospital, she plummeted to new lows. We watched, ashen, as she went from high as a kite to the lowest low. “I would sit in my flat, hour after hour, watching time pass and not knowing who I was,” she says now. “I didn’t know whether to stand up or sit down. I felt like a ghost. I couldn’t think, I had no hope. For the only time in my life, I thought I’d be better off dead.”

Her confidence was nonexistent. We suggested that she join a choir or get a dog, but she wasn’t interested. “My oncologist knew I was never going to recover by sitting in coffee mornings,” she says.

Instead she relied on a “circle of trust” (close friends, family, doctors), rebuilt her social life, and eventually went back to work on a perfume counter. “I laughed again but my confidence was still shattered,” she says.

I feared it would be that way for the rest of her life but, 18 months ago, something changed. “Darling, I’m going on a little course,” Mum rang to tell me. She had seen the first series of the The Marvelous Mrs Maisel, and was inspired. In the first episode of the Amazon Prime television show, Miriam “Midge” Maisel, a picture-perfect 1950s Manhattan housewife, arrives drunk and rain-drenched, in her nightgown, at the Gaslight comedy club, where she has spent months dutifully taking notes for her boring husband as he bombs at standup.

Reeling from the revelation that he has been having an affair, Midge strides on stage, seizes the microphone and owns the room.

“I was transfixed. I related to her,” Mum says. “I’ve been in rooms with people who think they are funny and secretly thought that I’m funnier, but kept quiet. I thought, I want to do that.”

With uncharacteristic decisiveness, my mother booked herself on to a standup course at the King’s Arms pub in Salford. It’s a popular spot on the amateur circuit, but also the kind of place where she won’t use the sole toilet because it’s not clean enough. Three years earlier, she had been unable to summon the confidence to get up from a chair, but here she was now, seizing life. I could see the boost that standup was giving her, but hated the thought of her exposing herself to ridicule when she was vulnerable. “I used to care what people thought of me because I was worried they misunderstood me,” she says. “But coming through my illness has taught me that everyone sees things differently. In my first comedy lesson, they put each of us in the middle of the room. People fired questions at you, and you had to say whatever came into your head. That was such a relief. I didn’t have to filter myself. It was just me and I didn’t have to worry about pissing anyone off.”

Her first gig, in front of the King’s Arms’ Sunday regulars, was a hit.

For a year, she wouldn’t allow anyone who knew her (myself included) to watch, but continued performing with newfound confidence. Then she took the somewhat irrational decision to fill the upstairs room of a local pub with 60 people she knew, and gave herself top billing.

On the night, she was visibly nervous, but her jokes were funny. I hated the idea that people would pass judgment on something she derived joy from, and found myself sliding down in my chair as my friend passed me a gin. I did laugh out loud (even at the one about dad filming her act “but not like he used to”).

But my overriding thought was, God, she’s brave. She looked strong, healthy, glamorous. “People say it takes guts,” Mum says. “To me, it takes more guts to rein it in. I find that much harder.”

As with Mrs Maisel, mum’s act is a two-fingers up to society’s expectations. And she has some sharp gags: “Now that I’ve experienced dating in my 60s, I’ve been thinking about a Love Island programme for the more mature,” Mum says. “Companion Island: everyone gets up for a wee in the middle of the night and date nights start at 5pm.”

Mum tells me afterwards: “It’s honest and it’s sweary and, yes, probably not what people expect from me.”

Now, even the messages the family get from her read like lines she is testing out: “The guy who is deciding whether I need to go to a memory clinic… I just sent him a recipe by mistake. I imagine he may get me a quick referral now.” She also has a WhatsApp group of comedy pals, called Live At The Apollo.

I asked her what the draw was. “I don’t consciously want people’s adulation, but when they laugh, I think, great – because I’ve made them happy,” she says. “That gives me a feeling of worth. It doesn’t give me a rush – it just feels as if I’ve found something that’s right for me.”

Mum admits that she worried my brother and I would think her foolish. “You’re the only people I care about bombing in front of. Other than that, I’m just sharing my unstraightforward life.”

And she’s pretty sure what unleashed this later-life comic potential. “I know, without a doubt, that my brain tumour was the catalyst. Maybe it was the trauma, maybe it was the drugs, maybe it was in me all along. I truly believe there is a capacity for good things coming out of bad.”

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