When Lincoln was seven years old, his family moved to Indiana. Later on they moved to Illinois.[3] In his childhood he helped his father on the farm, but when he was 22 years old he left home and moved to New Salem, Illinois, where he worked in a general store.[4] Later, he said that he had gone to school for just one year, but that was enough to learn how to read, write, and do simple math. In 1842, he married Mary Todd Lincoln. They had four children, but three of them died when they were very young.[5] Abraham Lincoln was sometimes called Abe Lincoln or "Honest Abe" after he ran miles to give a customer the right amount of change. The nickname "Honest Abe" came from a time when he started a business that failed. Instead of running away like many people would have, he stayed and worked to pay off his debt