The number of American military personnel in Vietnam increased dramatically, from 16,000 advisors in non-combat roles in 1963 to 525,000 in 1967, many in combat roles. They had two daughters, Lynda Bird, born in 1944, and Luci Baines, born in 1947. Johnson gave his children names with the LBJ initials; his dog was Little Beagle Johnson. His home was the LBJ Ranch; his initials were on his cufflinks, ashtrays, and clothes. He was described by friends, fellow politicians and historians as motivated by an exceptional lust for power and control. As Johnson's biographer Robert Caro observes, 'Johnson's ambition was uncommon—in the degree to which it was unencumbered by even the slightest excess weight of ideology, of philosophy, of principles, of beliefs.' At the same time as his vice presidential run, Johnson also sought a third term in the U.S. Senate.