By John Balson @JJBalson
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Videographer / director: Ruaridh Connellan
Producer: John Balson, Nick Johnson
Editor: Joshua Douglas
World-famous Hulk, who shot to fame last year in a viral video, weighs in at 181lb while tiny Mami weighs just five pounds.
But the difference in size and power hasn’t stopped them becoming firm friends who spend all day together.
Owners Marlon and Lisa Grennan of Dark Dynasty K9s bought Mami to see if they could train her as a protection dog.
They started by introducing Mami to their world-renowned pack of protection pitbulls when she was just a few weeks old and she has been part of the family ever since.
Lisa, 25, said: “Mami has a pitbull attitude. She thinks she’s a big dog, she’s tough and holds her own in the house.
“I don’t think she's really at danger playing with Hulk.
“He’s very aware of her size, he’s very gentle with her. They play really well together.”
Hulk and Mami eat, sleep and play together almost everyday at the family’s facility in New Hampshire, USA.
The only time they have to be separated is when Mami is in heat and Hulk’s instincts drive him to try and mate with her.
Experienced dog trainer, Marlon said: “It could be unusual to some people to have a chihuahua in with all these pitbulls but it’s not unusual to me.
“They are so comfortable because of the way they were raised, they have rules, boundaries, limits and balance. When you insert balance into a dogs life anything is possible. She’s part of the family."
Dark Dynasty K9s specialise in training elite protection dogs for the police, celebrities and billionaire clients around the world.