his grandfather / her grandfather / their grandfather / your grandfather
La niña está leyendo con su abuelo.
The girl is reading with her grandfather.
Su abuelo falleció pacíficamente.
Her grandfather passed away peacefully.
Su abuelo se suicidó en esa casa.
His grandfather committed suicide in that house.
Mary colgó la foto de su abuelo sobre la chimenea.
Mary hung the photo of her grandfather above the fireplace.
Es la viva imagen de su abuelo.
He/She is the spitting image of their grandfather.
Tom regresó al pasado, mató a su abuelo y desapareció.
Tom went back in time, killed his grandfather, and disappeared.
Su abuelo murió de cáncer hace un año.
Her grandfather died of cancer a year ago.