Kate Lawler practically vibrates with energy and curiosity, jumping with thoughts, feelings and opinions she has no qualms sharing. Whether it’s the micro-needling she had the day before, her skin still smarting (“I look a little bit Donald Trump!”), her love of a pisco sour or postnatal depression, she’s frank, funny and really quite dazzling.

You can see why she captured the nation’s attention in 2002, winning arguably the most iconic ever series of Big Brother. At just 22, not only was she the first female winner, her cohort also included Jade Goody, Alison Hammond and Adele Roberts. Twenty-three years on and people still stop her to ask about it, and whether she’d do the celebrity version. “I always say no, because I had such a great experience, and nothing could top the experience I had of winning,” she says. “People look back at it with nostalgia and really fond memories. As time has gone on and other series have been and gone, you realise what a great series 3 was and what excellent housemates were cast.”

We’re chatting because she’s teamed up with Adaptil, who make calming products for anxious dogs. Lawler, 44, adores her two, Baxter and Shirley, who have struggled with fireworks and public transport. “They are never not happy to see you,” she says. “They bring this level of internal joy that I can’t describe. Dogs are almost like magic.”

Hers are considered siblings to her four-year-old, Noa, who she shares with husband Martin ‘Boj’ Bojtos. “Our daughter’s at a stage where she’s asking for a sibling, and I’m like, ‘You’ve got two: Baxter and Shirley,’ and I’m so sorry, but I can’t do that again,” she says with a laugh. “I don’t know how anyone does it again!”

Lawler wrote about her postnatal depression in her bestseller, Maybe Baby: On The Mother Side. A self-confessed “oversharer”, Lawler had a great pregnancy and birth. “I had this vision of me being on social media, like, ‘Look at me with my baby, isn’t it great?’ I had no idea I would be crying to my Instagram family saying, ‘Why? What have I done? Help!’”

Sharing what she went through made her realise how many others were in the same position. “I thought, if a handful of people in my corner of the internet are going through this, then I need to help other people who might not be aware that postnatal depression is a thing,” she says. “It’s normal, and it’s also perfectly normal to love your child more than anything you’ve ever loved in your life, but also find parenting the most difficult thing you’ve ever done, and to not enjoy aspects of it.”

Three years on from Maybe Baby, she says: “I absolutely love being a mum and I remember, in that first year, I never thought I would say that – I couldn’t see further than what was right in front of me.” She adds: “I’m in awe of just how interested Noa is in the world and how pure she is. I’m like, ‘Oh, bollocks!’ but if something goes wrong she keeps saying, ‘Oh biscuits!’ I’m so pleased I had her. I’m so pleased I waited as long as I did as well, because I feel like I’m the best mum I can be because of my age and life experience.”

Parenting and ageing have shaped how Lawler cares for her mental health. “Life was a lot simpler when I was in my 20s,” she says. “I’ve been through postnatal depression and my daughter is my number one priority. So if I am mentally okay, the family unit is mentally okay.” While she’s not into sitting still and meditating (“No thank you! My meditation is dog walking!”) she’s slashed her alcohol intake (apart from the odd pisco sour and a glass of red with Sunday lunch), and goes big on mindful exercise, which stops her mind racing. “It really is great for my mental health, because I’m so present in the moment,” she says of hot yoga and Pilates. “You’re taught to be thankful for your body for allowing you to do all these exercises.”

Sport has always been part of her life, thanks to a sporty dad who played cricket and football, and holidays in the Isle of Wight and Bournemouth spent having “the most fun with a tennis ball on the beach, throwing, catching” with her siblings. Even in her 20s, exercise stuck. “I was a wild child. I did a lot of drinking. The exercise was the one constant in my life – kickboxing, running,” she says. “Now I’m in my 40s, I’m perimenopausal, so I’m doing a lot of weights.” She eats well too. “I’m a big carb person, so almond pastries, sweet buns, cinnamon danishes, they’re my weakness. But I’ve always said, ‘Everything in moderation’. I’ll never restrict any foods,” she says. “I’m like 80% healthy and 20% naughty!”

She and Boj are also working on their work/life balance. “We’re actually really bad at it. We are both workaholics while being parents, which in itself, is a full-time job,” she says. “We don’t have time to sit and watch a boxset and I want us to be better at that. We recently decided to do a podcast together (Boj & Kate Have A Lot On Their Plate), which takes up a lot of our time. So we don’t make it easier for ourselves!”

That said, Lawler seems able to squeeze more silliness and joy out of things than most. “Being silly is what makes mine and Noa’s relationship so special. I am silly. I’m like a child actually. I don’t know why I can’t grow up. I just love messing around,” she says giddily. “Boj is more serious, but sometimes he says, ‘I quite like it because you taught me how to be silly’.”

Kate Lawler is an ambassador for Adaptil, which creates products that help dogs cope with stress and anxiety.