He rushed to help her, braving the danger of driving through flames, but it was too late by the time he arrived.
Manuel was the first person to reach the road where 47 people died Saturday, burned alive in their cars. The blaze has killed a total of 63.
The 23-year-old found his mother's body just 500 metres (yards) from the family home.
Two days later, in heat that hit 36 degrees Celsius (97 degrees Fahrenheit), he, his father and a neighbour set about burying animals that had succumbed to the flames, including a cat and goats.
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The village has around 50 houses, stretching along a narrow, steep road that spills into a valley now covered in ashes and blackened trees.
Manuel told AFP that he was in the coastal city of Figueira da Foz, around a hundred kilometres (62 miles) away, when she called.
He hastily made his way to Pobrais, using an alternate route and even driving through flames in a desperate attempt to save his mother.
'Everything burned'
"Everything burned, even my work," said the young man, who works in the wood industry.
Next to him, his father Jose Manuel is unable to talk about the tragedy. The farmer, 57, could only say that that his wife, who earned a living as a cleaner, had left the village in a car with her cousin who also died on the fateful national route 236 that links Figueiro dos Vinhos to Castanheira de Pera.
His neighbour, Vitor Neves, was married to the 38-year-old cousin. At the time of her death, Neves was fighting the same fire, 35 kilometres away.
He, too, tried to reach the village but also arrived too late.
Pobrais lost 12 villagers in the fire. Eleven people died on the main road, trapped by flames coming from all directions as they tried to flee.
Neves said he believes the disaster could have been avoided.
"The village exit should have been blocked. If people had stayed in their houses, they would have survived," he said.
Neighbours across the street did survive, taking refuge in a water tank set up in front of their door.
Maria do Ceu Ferreira, her retired husband and two daughters in their 30s saw the fire sweep over their heads.
"Without the water tank, we would be dead," said the 56-year-old woman, who had no voice after screaming during those tense moments.
She has no idea how long it lasted.
"It felt like an hour, but I don't really know, we completely lost all notion of time."
She said she somehow felt that those who left the village were putting their lives in danger.
"When we saw people heading for the road, we begged them to stay with us in the water tank but they were blinded by panic," she said.
Among the people who stayed in the village, a man in his 50s burned to death in his home.
The house at the lower end of the village and closest to the forest, was reduced to ashes, along with the rest of the surrounding valley and hills.
"I have been a fireman for 26 years and I have never seen anything like it," said Antonio Coutinho, who works with Vitor Neves with the forest fire fighting crews.
"No one could have imagined the fire would move so fast. It engulfed the entire valley in a matter of minutes."
