Sadie Sink was 18 in Fear Street: 1978 when she played the character 'Christine 'Ziggy' Berman'.
That was over 3 years ago in 2021.
Today she is 22, and has starred in 10 movies in total, 4 of those since Fear Street: 1978 was released.
In Fear Street: 1978, I think Sadie Sink looks: