Lots of couples invest in a puppy to test the waters before they have a baby.

But Josh Hartnett has bravely chosen to bring up both at the same time, as he stepped out in Hampstead to walk his new puppy on Tuesday. 

There was no sign of girlfriend Tamsin Egerton, 27, who was no doubt at home looking after their newborn baby.

Hollywood star Josh, 37, cut a cool figure in stylish black bomber jacket won over a navy v-neck jumper and matching t-shirt.  

He teamed the threads with a a black belt, grey jeans turned up at the ankle, white socks and a beat up pair of navy Nike trainers.

The actor added a hipster edge with a black beanie, clear-rimmed specs and trendy facial hair.

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Hipster: Hollywood star Josh, 37, cut a cool figure in stylish black bomber jacket won over a navy v-neck jumper and matching t-shirt

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Growing up fast: Despite being a puppy, the black and white pet looked to be a fair size as it trotted sprightly by Josh's side on a loosely held leash

Despite being a puppy, the black and white pet looked to be a fair size as it trotted sprightly by Josh's side on a loosely held leash.

Earlier this month, Josh and Tamsin were spotted leaving St Mary's Hospital in London, following the birth of their first child.

The couple are thought to have met on the set of The Lovers in 2010 but reportedly didn't become an item item until 2012's Singularity, where they starred opposite each other again.

Josh has previously been linked to Hollywood actresses Scarlett Johansson, Amanda Seyfried and Mischa Barton though he has remained notoriously private about his current relationship.

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On trend: Josh teamed his jacket with a a black belt, grey jeans turned up at the ankle, white socks and a beat up pair of navy Nike trainers

Speaking to USA Today in May this year, Josh explained: 'I purposefully didn't want people to know too much about my personal life because I think a lot of people give it away for free.

'I think if you spend too much time courting people's attention into your personal life, you lose your ownership of it.

'That's why I make sure my life is my own. I was not a dumb kid. I was a little bit wary of this business. I saw what it could do to people pretty quickly.'

Tamsin, meanwhile, has previously insisted that Josh is one of only three boyfriends she's had, telling The Daily Mail in 2013 that she's 'not interested in serial dating; I’d honestly rather be single.'  

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Daddy cool: The actor added a hipster edge with a black beanie, clear-rimmed specs and trendy facial hair

Read more: http://www.dailymail.co.uk/tvshowbiz/article-3361367/First-time-father-Josh-Hartnett-looks-cool-specs-beanie-takes-break-parenting-duties-walk-new-puppy.html#ixzz3uQ3wwnWp 
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