They couldn't have gotten someone better to play older Harper? Rachel Dratch did a decent job handling Harper's mannerisms, but she doesn't look like she could even be related to Jennifer Stone, let alone an older version of her.
"Does your society have any other adjectives besides 'great'?" - Pvt. Church
We all have our opinions on who looks similar, who looks different. You must have heard of this sometime in your life...
Whoever is in charge of casting, to them Rachel was a similar looking person to Jennifer.
Pretend something pithy is here.
http://i39.tinypic.com/2s8mluo.jpg
I'm looking at the high school senior photos of my five siblings and me on the wall to my left. I don't see much in our facial features that look like our parents.
Who knows why casting folks choose certain actors to play adult versions of teenagers -- or to play the parents or siblings? Rachel Dratch was still on "Saturday Night Live" when "Future Harper" was recorded (2009) so familiarity to the audience might have been a factor. She also guest-starred on other networks' shows at the time.
Yeah, I know filankey is not a word, but it's gonna catch on.