When it came time to celebrate her husband Steve Howey's 40th birthday, Reverie star Sarah Shahi, 37, enlisted the help of Howey's on-screen wife Shanola Hampton to get the cast of their Showtime series onboard. "Shanola is basically my sister wife," Shahi (right) tells PEOPLE. "She helped me organize everything on the Shameless end."
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Keeping It a Surprise
"I'd been planning this thing for months and he has no clue," Shahi, who has three children with Howey, says of inviting 80 of her husband's closest family and friends to hop on a party cruise around Marina del Rey, Calif. on Saturday. "When he mentioned having a party I said, 'Give me a list of a couple people and I'll try to throw something together — but I'm busy with my show!' In the past week he kept trying to get information out of the nannies and of Shanola."
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A Family Affair
"My whole family came into town and we drove over together," says Shahi. "Steve is kind of shy and doesn't always love big parties but I knew he would love this one."
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The Big Reveal
"One of the reasons Sarah Shahi is the love of my life is that for my 40th birthday she surrounded me with the love in my life," says Howey.
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A Sure Bet
"I rented out this huge yacht so we could spend the night dancing and gambling," says Shahi.
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A Sailin' Man
"Steve grew up on a sailboat, so that was the inspiration to do the party on a yacht," says Shahi.
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Howey with his Shameless castmates.
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A Cake to Remember
Shahi ordered two special cakes for the celebration...
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"I got these really cute pictures of him as a kid and put them on the cakes," says Shahi. "On one of them is when he fell into the toilet and another is where he's wearing a motorcycle helmet and cape."
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A Lot to Celebrate
"We've been together for almost 15 years, we have three children. I just wanted to throw him this celebration of life and love," says Shahi (with Howey and son Wolf, 8. Not pictured: twins Knox and Violet, 2).