Reese Witherspoon's daughter was the belle of the ball, quite literally. On Saturday, November 25, Witherspoon's not-so-little girl Ava Phillippe made her debutante debut, attending the 5th annual Bal des Debutantes in Paris in a gold Giambattista Valli Haute Couture ballgown. While the mother and daughter have been known to coordinate their outfits, for Ava's big night, Witherspoon opted for a chic black dress that let her daughter shine. Witherspoon looked like the proudest mom as she posed side-by-side with her twin daughter who was one of 20 young women who were introduced to society at the very exclusive ball, which is part debutante ball, part fashion show.