What we know about John's family history: John has thalassemia major. Both of John's parents have normal red blood cells. John also has a brother and a sister, but neither have been tested for the thalassemia trait. John's wife, Linda, has normal red blood cells. Both of Linda's parents have normal red blood cells. Linda's maternal grandfather (her mother's father) has normal red blood cells, while her maternal grandmother (her mother's mother) has the thalassemia trait. Linda's fraternal grandfather (her father's father) had thalassemia major, while her fraternal grandmother (her father's mother) had normal red blood cells.