Abigail Christine Milliet was born on August 13, 1996 in Denton, Texas. Abby has two sisters, Nicole and Emily.

In 2005, Abby competed as a level seven, where she placed sixth in the all-around and first on uneven bars in the bronze division of the Texas Level 7 State Championships. She moved up to level eight in 2006. Abby won the Kurt Thomas Invitational. She advanced to level nine in 2007. Abby qualified to the Level 9 Regionals. After the level nine season, she competed as a hopes pre-elite at the US Challenge. Abby qualified to the 2007 National TOPs Testing.

In 2008, she competed level nine and hopes pre-elite. She finished third on vault at the North District Qualifier. In May, she finished second overall at the US Challenge. Abby moved up to level ten and junior international elite in 2009. At the end of February, she achieved her junior international elite score at the Palm Beach Invitational. She finished fourth on uneven bars at the Level 10 State Championships. A week later, she made her international elite debut at the American Classic. At the US Covergirl Classic in Des Moines, Abby finished 13th in the all-around and fifth on vault. There, she qualified for the US National Championships.

Currently, Abby is a junior international elite gymnast from Denton Gymnastics in Texas. She is training under coaches Aurel and Rodica Lazar. Currently, Abby is preparing for the 2010 US Covergirl Classic in Chicago, IL and VISA Championships in Hartford, CT.