Abby Ryder Fortson was 6 in Ant-Man when she played the character 'Cassie Lang'.
That was over 8 years ago in 2015.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 15, and has starred in 7 movies in total, 6 of those since Ant-Man was released.
In Ant-Man, I think Abby Ryder Fortson looks: