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JIMMY FALLON & GARY
"She's a girl named Gary," says the Tonight Show host, who first met the "cute, fluffy and fun" purebred when she came on his then Late Night show as a puppy, dressed in a suit, for a skit. And, says Fallon — who just released his latest children's book Everything Is MAMA — Gary is also a big hit with kids, especially his daughters Winnie Rose, 4, and Frances Cole, 2, with his wife, Nancy Juvonen. "To Franny I go, 'Who loves you?' And she goes, 'Only Gary!' And she laughs at her joke. They're besties."
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ERIC MCCORMACK & PENNY
McCormack loves all his pets; he has a 9-year-old terrier mix (which his son Finnigan, 15, named Scruffy) and Hunter, the cat he and his wife, Janet, have had for three years. But the actor who stars on Will & Grace and Travelers has a special place in his heart for his pup Penny. "It always said 'boxer' because no one wants to say 'pit,' but we knew," he says of getting Penny from a rescue. "Pit mixes can be great. She is really a gentle giant."
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SCOTT EASTWOOD & FRED
"He's a really good dog. He's playful and loving, and he likes to nibble my ears," says the Pacific Rim Uprising star, who has been co-parenting Fred since the Lab's birth, with his best friend and roommate. "After a stressful day, when a dog licks your face, you realize things are okay. No matter what is going on in your life, when you get home that dog doesn't care. He loves you unconditionally."
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WIZ KHALIFA & MAX B
"I've never had a dog that drools like him, but that's my baby boy," says the rapper, adding that Max B makes his son Sebastian, 4, jealous because "he wants to be the baby." Luckily Max B and Khalifa's other dog, Vincent, a 3-year-old French bulldog, get along, hanging together at home and on tour with Khalifa. "They're party animals," says Khalifa, who just released his Laugh Now, Fly Later mixtape. "They live a full life."
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BOBBY FLAY & NACHO
"He's doglike for a cat," says the Food Network star, chef and author of Bobby Flay Fit. "He's incredibly affectionate with me and will follow you around like a dog would." Flay says the 20-lb. feline (and Instagram star with more than 120,000 followers!) is also a "food connoisseur." "He's always with me when I'm cooking. If I make a piece of striped bass, I'll cook the end for him as a little treat."
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DENIS LEARY & BOWIE
The actor and author of Why We Don't Suck first fell in love with Bowie's "floppy Muppet-like" look and soon discovered he was the perfect best friend. "He loves to swim, he's game if you just want to run, and he's like a wide receiver in terms of catching a ball," says Leary, who named Bowie after one of his favorite rock stars. "I like a good rough-and-tumble dog. And he's very attached to me, so I'm attached to him."
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DR. EVAN ANTIN, HENRY & BLUE
"Henry is a rescue and just precious. He's got this perma-puppy thing going on," says the PEOPLE Pet Vet. And Blue, who was found abandoned on a roof, is "superathletic and really fun to play with." Dr. Antin, who sees patients at Conejo Valley Veterinary Hospital in Southern California, also has another cat, a lizard and a tortoise, who all get along well. And while he thinks about bringing more pets home, his priority is "giving these guys the life they deserve," he says. "I need to be realistic!"
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