Maybe a point to keep in mind is that a girl of 17 and a woman of 23 don't necessarily have the height difference that males have at the same ages. Differences are more subtle - a girl of 17 might have less defined facial features, less difference in the breast/waist/hip ratios, but put her in a formal dress next to a 23 year old and many wouldn't be able to tell which is older or by how much. My daughter reached her "adult" height at 14 years old (she's now 22), my youngest son (now 17) is still growing.