But tragedy struck when the 28-year-old sergeant died in his Baghdad barracks in Christmas, the cause of which remains unknown. His family decided one way to ease the grief would be to transport the dogs home, something they reached out to their homestate senator, Carl Levin, the ranking member of the House Armed Services committee, to help arrange. An airline and animal organization helped coordinate the 6,000-mile trip.
"It's second to having Peter come home on his own," the soldier's sister said. "If we can't have Peter, then at least we can have his dogs."
Dennis could be home from Iraq as early as March, his mother said. The dog no longer will have to contend with fighting to survive in the war-torn country, Dennis wrote in an e-mail, but instead will get to bask in the sun on the sunny beaches of San Diego.
It's a day Dennis' mother said she can't wait to see.
"He's always been a big dog lover," she said. "He's supposed to be this big, tough Marine, but he's really a softy."
ABC News' Barbara Pinto contributed to this report.