Andrew and Rachel Jackson actually served as guardians for numerous children over the years, including one Native American (see Michael's post on this topic). The one they adopted, and who inherited Jackson's Hermitage, was Andrew Jackson, Jr. Now I've posted on his wife, Sarah Yorke Jackson, so I thought it was time to post a little on him:
In 1808, they took in an infant; one of a set of twins, of Rachel's brother Severn Donelson and his wife Elizabeth and raised him as their own. They named him Andrew Jackson Junior (1808-1865). Although some accounts suggest they took the child because of the mother's ill health and inability to care for her children, the reasons for the adoption are not clear. Andrew Junior and his twin, Thomas Jefferson Donelson, remained close all of their lives. Andrew Junior attended school at Davidson Academy and the University of Nashville. When Andrew Jackson became President, Andrew Junior assumed management of the Hermitage farm. Andrew Junior married Sarah Yorke of Philadelphia on November 24, 1831. Although Junior's financial woes brought Jackson grief in later years, he was always a devoted father.
I find it very interesting that they adopted one of a set of twins.