Since I have embraced the philosophy that “only the PT, Rogue One and the OT are Canon”, now I can take more liberties when it comes to my own head-canons, as I don’t have to take into account nothing but the movies themselves. Therefore, I have decided that I want to change Anakin’s age in Episode I and extend the Clone Wars a little more. Firstly, Anakin was not 9 in Episode I, he was 10. Secondly, the time gap between Episode II and Episode III is not 3 years, but 6 years. So, Anakin is 20 in Episode II and 26 in Episode III, while Padmé is 30 in Episode III, and Obi-Wan is 41.
Also, since I don’t have to take into account nothing but the PT, Rogue One and the OT, now I can fully embrace the idea that the Stormtroopers from the OT are the Clone troopers from the PT, and I can totally incorporate this idea in my head-canon. Therefore, the Empire never started to recruit normal citizens into the Imperial Army, Kamino continued to provide Clones for the Empire until its defeat, and all the Stormtroopers we see in the OT are clones of Jango Fett, just like the Clone troopers from the PT. This is why Leia said: “Aren’t you a little short for a Stormtrooper?” The Stormtroopers are all Clones, so they all have the same height.