Was Teen Goku (23rd) fully grown?

[Let's Go Fearless!]

The announcer probably shrunk.

He's old by the time of 28th budokai.

 

[Void Lumina]

I always just thought of it as a Saiyan Trait seeing as they age slower compared to humans. I would place a Saiyans Prime around 35 years old, because 15 year old Goku was HELLA Shrunk. Not to mention it happened with literally every other Saiyan in the series, look at Vegeta, Gohan, Goten, Trunks, Broly, etc. All small shrinks until they are about age 17-19 and then they continuously grow taller until they peak.

Which also lead me to believe that Future Trunks did change his past self causing him to have more Saiyan Dominant traits than him, which explains why our 13 yr old Trunks he is so much shorter than the 13 yr old Future Trunks.

 

[Hector]

We have to see his penis. If it was large, then he was indeed fully grown.