Lona cannot have age progression or a “developed” body for two reasons:
-Everything happens in a very short time span, from the beginning of the game to the ending.
-She is an adult, yet she suffers from malnutrition and that is quite clear from the beginning of the game, a malnourished physique usually looks like hers.
That's leaving aside how complex it would be to design an age progression system in a game like this with all the variables that entails, and the fact that it's unrealistic for a poor woman with little access to food to have huge boobs and wide hips.