Brazil ghosts

This from the person who sent it in…

“I’ live in the city of Santos, in Brazil. The  photos were taken recently (on March 10th and 12th) by a friend of mine on a mobile phone without flash, inside the house where my  father and grandfather lived years ago.  My father died in 1981 and my grandfather, in 1951.  The house is situated in the city of Ilhabela, state of São Paulo, Brazil, where my father, my grandfather and I were born.    After my father’s death, my sister and I became owners of the house.
The photos show unclear images.   When the photos were taken,  there was nobody  inside the house, but the person who took the photo and a friend of him. They are young men, totally different from the images shown.
My sister and other people say the images look like my father (dressed with a white shirt) and my grandfather (with dark clothes).  I’m not sure about it and I don’t believe in ghosts. I was not present when the photos were taken, but I think the two people, who were in the house, are credible.    They assured me they he aren’t joking.   They saw the pictures just after they were taken, so it couldn’t be a trick made by them.  They were surprised and scared. They didn’t understand what happened.”