How is life in nappy valley?

It's lovely. Florence is a bit of a textbook baby. I've only ever seen her cry real tears once. She is four months old today - we sang Happy Birthday to her this morning; is that really ridiculous? I'm also a step-mum. My husband (the actor Tom Ellis) also has a child, who's 3 1/2. She was really excited to have a new baby around.

Are you getting much time to yourself?

I went to see Oasis perform twice last weekend, as they're friends of ours. The baby was looked after by her Uncle Kev, my brother.

Did you read every book under the sun before you were expecting?

No, I've been doing most things from instinct. I had lots of babies around me when I was younger. I was always changing nappies, burping them and winding them. Also, my mum came to live with us for two weeks, helping with the cooking and so on, which was great. It's so easy to neglect yourself when you've got a little one. We also had a night nanny who taught us all about routines.

Are you still in the babymoon period?

I'm very aware of gushing, because it's really not that interesting for anyone else. Tom and I gush to each other, but I think that's OK. He is absolutely relishing it all. We've had four months with just the three of us at home. You can't ever get that time back, so I feel really lucky.

Tom is a bit of a toyboy, isn't he?

He's eight years younger. Mentally he's much more mature, and I'm the child in the relationship, so it works! Other people seem to be bothered by the age gap, but it doesn't even cross my mind.

You have just started work on the second series of ITV1's The Fixer. Any guilt?

I'll miss Florence, of course, but I'm ready to go back. I'm not desperately ambitious any more, but I love what I do. What's lovely in this industry is that you can work hard, doing long hours, then take a month or two off. I always knew that I wanted kids.

What was your childhood like?

I'm a child of the Seventies. My dad's a taxi driver, and my mum's a financial adviser. We always had an open house, full of waifs and strays, with someone from another country who had just escaped from a war in our front room!

So how did you catch the acting bug?

I trained as a dancer from a very young age and then started doing drama classes. It's quite hard to be satisfied by anything else once you get hooked.

Now that you are back at work, are you going all out to get back in shape?

I'm doing it quite slowly with a bit of Pilates and I see my trainer once a week. I also have a Power Plate, which I use about three times a week. I keep saying to all my friends that we should set up a netball team.

Are you on a strict diet?

No carbs after 6pm, but that's it. I'm quite slim naturally and have never been much of a dieter. But we're all susceptible to getting a bit bigger after too much of the good life.

So it's control pants all the way?

I've got a bit obsessed with treatments. When you become pregnant, you feel like you're not in your own skin. I had one of those Universal Contour Body Wraps that is supposed to take an inch off everywhere. It really worked! It's good even if it's just to look in the mirror and think, “OK, losing that weight is achievable”.

Would you ever go under the knife?

No, because I associate it with hospitals and being ill. Speak to me when I'm older though!

Your famously husky voice suggests an inner party animal

I haven't actually drunk alcohol in about two weeks. There's so many calories in it. I used to be a social smoker when I was drunk and would go around nicking cigarettes off people. But my voice has been like this since I was about 4!

Sounds like you've got your feet on the ground

I don't really live a showbizzy life even though you always see me pictured out with people like Liam Gallagher or Kate Thornton or whoever. It's all kids and nappies nowadays.

Any plans for more children?

Yes, but I'd like to enjoy this one a bit first. I have a brother and sister and there are lots of cousins around. We're all quite close.

Is there anything that keeps you up at night?

I'm pretty calm in general. But I was worrying while I was pregnant about everything being OK. I'm a bit superstitious and didn't run out and buy baby things, like a car seat, until the last minute.

Do you have a spiritual side?

Definitely. I read every single self-help book under the sun during my twenties. I wasn't having a tough time, it was probably a throwback to my hippyish upbringing. They're all hidden away somewhere, thank God. But I think that spirituality is really all about your inner instinct leading you. I was brought up a Catholic. My sense of belief in God grows stronger when I'm going through life-changing events.

Anything you'd like to change about yourself?

I'd like to stop time for about 25 years. Not because of the ageing process, but because everything's so brilliant at the moment. I'd like it to last a bit longer.

INTERVIEW: HARRIET ADDISON

Tamzin Outhwaite is an ambassador for Oral-B

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