King saw his father's proud and unafraid protests in relation to segregation, such as Martin, Sr. refusing to listen to a traffic policeman after being referred to as "boy" or stalking out of a store with his son when being told by a shoe clerk that they would have to move to the rear to be served. When King was a child, he befriended a white boy whose father owned a business near his family's home. When the boys were 6, they attended different schools, with King attending a segregated school for African-Americans. King then lost his friend because the child's father no longer wanted them to play together. King suffered from depression throughout much of his life. In his adolescent years, he initially felt some resentment against whites due to the "racial humiliation" that he, his family, and his neighbors often had to endure in the segregated South. At age 12, shortly after his maternal grandmother died, King blamed himself and jumped out of a second story window, but survived. King was originally skeptical of many of Christianity's claims. At the age of thirteen, he denied the bodily resurrection of jesusduring Sunday school. From this point, he stated, "doubts began to spring forth unrelentingly