Ariel Winter was 9 in Horton Hears a Who! when she played the character 'Additional Voices (voice)'.
That was over 16 years ago in 2008.
Today she is 26, and has starred in 51 movies in total, 37 of those since Horton Hears a Who! was released.
In Horton Hears a Who!, I think Ariel Winter looks: