The Thatcher family initially emigrated to Utah in 1847. At some point after their arrival, they continued on to California and made their home in San Bernadino. In 1857, when the Saints in outlying settlements were asked to return to Utah, Hezekiah Thatcher led his own little company from California, leaving in mid-July, as far as Carson City, Nevada. There they joined up with another group returning to Utah. The two groups organized under Perrigrine Session's leadership.
Alley's given name appears as "Alena" in some sources.