>>15749719Let's take a look at that statement, in a roundabout manner.
Shauna is roughly the same age as the protagonist, correct? After the protagonist has become the Champion of Kalos, Looker of the International Police Bureau will take him/her on as his apprentice. Your first case under Looker introduces you to a girl named Emma, who is treated by literally everyone else as your junior.
Later, Emma is confirmed to be a "healthy 16-year-old girl".
Which means that the Protagonist is canonically at least 16, probably slightly older, as is Shauna.
It doesn't even matter that this is 4chan, saying that she's 10 is just wrong.