Leao refuses to leave the grave of her owner, Cristina Maria Cesario Santana, in Brazil (AFP/Getty Images)
The dog, Leao, sat next to the grave of owner Cristina Maria Cesario Santana for over two days.
Ms Santana died in the mountain vacation city of Teresópolis, which saw some of the highest numbers of deaths resulting from the catastrophic floods and landslides.
They have claimed at least 655 lives so far and left many people homeless.
Brazil's army on Monday sent 700 soldiers to help throw a lifeline to desperate neighborhoods that have been cut off from food, water or help in recovering bodies.
Leao sits alongside dozens of graves that were dug for landslide victims in Teresopolis (AFP/Getty Images)
Troops have already set up at least one bridge in Teresopolis, officials said, but at least 10 main highways remain blocked in the rugged area north of Rio where the slides hit, hampering efforts to move in the heavy machinery needed to begin massive clean up efforts and eventually dig out bodies stuck under tons of mud and debris.
The troops plan to set up mobile bridges that can span 200 feet (60 meters) and are robust enough to support the hundreds of pieces of big equipment needed in clean up and recovery efforts.
Days of heavy rains unleashed tons of earth, rock and raging torrents of water down steep, forested mountainsides on Wednesday, directly into towns that are weekend getaways for the Rio area.
Rescuers had yet to reach about 20 neighborhoods, though a break in rains and better visibility allowed about 12 helicopters to begin taking supplies and firefighters in, while shuttling injured survivors out.
A view of a destroyed street following a landslide in Nova Friburgo, 130 km north of Rio de Janeiro (AFP/Getty Images)
But pilots said flying was still treacherous in the area full of jagged mountain peaks, where there are few safe landing zones and power lines are draped between peaks through seemingly clear space.
'These are the most challenging conditions I've flown in,' said Adalberto Ortale, a helicopter pilot for Ibama, the enforcement branch of the Environment Ministry. 'The majority of people doing the flying are not from here and you have to orient yourself on the fly.'
Brazil's minister of science and technology, Aloizio Mercadante, said 5million Brazilians live in some 800 areas at high risk for mudslides and floods across the nation, but that it would take at least four years for a nationwide alert system to be in place, the Folha de S. Paulo newspaper reported on its website on Monday.