Thats a neat photo. Looks to be a late 30's to 40's car, and it looks like a coupe or club coupe. Can't tell which brand though.
Us teenyboppers took those cars in the 50's and stuck Caddy and Olds engines in them to make hot rods. Did you notice THE taillight? Mechanical turn signals were still in the future. You actually had to stick your hand out the winder to signal for a turn. Hand down meant slow or stop, hand horizontal meant left turn, hand vertical meant right turn. You actually had to pay attention in those days.
By the way, not to be disrespectful, but Grandma was a Hottie.
Best wishes, Bill