[27] By 1752 he had bought almost 1,500 acres (600 ha) in the Valley and owned 2,315 acres (937 ha).[28]
In 1751, Washington made his only trip abroad when he accompanied Lawrence to Barbados, hoping the climate would cure his brother's tuberculosis.[29] Washington contracted smallpox during that trip, which immunized him and left his face slightly scarred.[30] Lawrence died in 1752, and Washington leased Mount Vernon from his widow Anne; he inherited it outright after her death in 1761.[31]

Colonial military career (1752–1758)
Lawrence Washington's service as adjutant general of the Virginia militia inspired his half-brother George to seek a commission. Virginia's lieutenant governor, Robert Dinwiddie, appointed George Washington as a major and commander of one of the four militia districts. The British and French were competing for control of the Ohio Valley. While the British were constructing forts along the Ohio River, the French were doing the same—constructing forts between the Ohio River and Lake Erie.[32]
In October 1753, Dinwiddie appointed Washington as a special envoy. He had sent George to demand French forces to vacate land that was being claimed by the British.