Family has identified the men as Bobby O'Neal and his grandfather, former Colleyville Mayor John Andrews.
The fire in the 2200 block of Oak Knoll started around 7 a.m. Thursday. When firefighters arrived, part of the roof of the home had already collapsed.
There were four adults inside the at the time. Two people escaped - the wife of the homeowner and their adult daughter.
Fire officials said they attempted a rescue of the second floor of the two-story home, but the fire was too and they had to retreat.
Relatives said Andrews was unable to get out of his bed without assistance.
"The mother was very concerned about the . She was still trying to get in there and she was trying to make access back into the structure," said Colleyville Fire Chief Brian Riley. Out of concern for her safety, firefighters held the wife back.
Fire crews from Colleyville and six other cities helped with the blaze.
The structure was destabilized due to the fire, which slowed the recovery effort.
The cause of the fire was not immediately known.