Barbara Gordon: Batgirl/Oracle Appreciation 2021

[Restingvoice]

I don't remember when Babs was mentioned to be 25 years old other than the 70s Bat Family series.

Barbara debuted in January 67 as an adult.
In December 69, Dick went to university.
Batman Family in 1975 portray Barbara as 25 year old congresswoman. Dick is already in university, with a girlfriend.
In March 81 Bruce was mentioned to be 28 years old.
Then Dick was 19 when Jason became Robin in 1983-ish.

So it's not a big aging timeline. At least 3, at most 4 years.
So at most Babs only aged from 23-24 to 25 to 26 years old. There won't be a visible difference physically.

Dick looks like he aged a lot because before college he's drawn like a teen, then in university, he got hot, lol. His body becomes more visibly muscular.

Also, even if Babs started at 25, there wasn't any plan to age Dick up at that time, as far as I know. It was the second season of Batman 66 tv series I think but sales are going down for comics, so they sent Dick to college because they want to bring back Bruce as a solo hero and increase sales... if I remember correctly.