Bruce Willis isn't as tough as he looks!

Though he plays a gun-toting former black-ops CIA agent in Red 2, the 57-year-old actor showed off his softer side while spending time with his 7-month old daughter, Mabel, in between takes in London. Nov. 2. Willis smiled wide as his little girl -- wearing a denim ensemble with floral details -- giggled on the set of the action movie, which also stars John Malkovich, Mary-Louise Parker, Anthony Hopkins, Catherine Zeta-Jones and Helen Mirren.

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Mabel is the first child for Willis and his wife, British model Emma Heming, 34. "Two bottom teeth. Check. Two front teeth. Coming in! Always exciting for this first-time mom," Heming tweeted Nov. 11.

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Willis has three other daughters -- Rumer, 24, Scout, 21, and Tallulah, 18 -- with ex-wife Demi Moore, 50. Earlier this year, Willis shared some lessons he's learned as a father with Esquire. "Take responsibility for when you are wrong. They hear you own up, and they learn to own up," he said. "You have to give them a code, beginning with things like, 'Don't bite people.' That becomes something like, 'It's not okay to be mean. Ever.' That was our watchword when the girls were younger."

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Most importantly, Willis told the magazine, is to make his daughters crack up. "You gotta do the drool-take, gotta make them see that goofiness is still safe," he said. "You have to make them laugh at you."

This article originally appeared on Adorable! Bruce Willis Bonds With Daughter Mabel, 7 Months, on RED 2 Set