Lincoln sent Hay away from the White House on various missions. In August 1861, Hay escorted Mary Lincoln and her children to Long Branch, New Jersey, a resort on the Jersey Shore, both as their caretaker and as a means of giving Hay a much-needed break. The following month, Lincoln sent him to Missouri to deliver a letter to Union General John C. Frémont, who had irritated the President with military blunders and by freeing local slaves without authorization, endangering Lincoln's attempts to keep the border states in the Union.