Parents and children, especially tweens and teenagers, often worry when they notice that they are shorter than many of their peers and classmates of the same age. While there are many medical conditions that can cause children to have short stature, most children who are short are normal. This is one time when kids can blame their parents, or at least their genes, for something. Most children are short because they have short parents.
Teenage girls will experience many physical and emotional changes, including breast development, pubic hair growth, and their first periods. Every girl will develop at a different rate than her peers. Typically, puberty can begin as early as age 8, some girls may develop earlier and some later.
By all means, I encourage you to try having those discussions and to make a mental note of when you would choose to walk away instead. I mean, I get where it comes from but it's so ridiculous. Ask her if her parents buy their underwear from a bookstore.
If your heart longs for children, a family and love- why should you stop yourself holding out for some mystical Mormon man to swoop you off your feet. When out on a date with a Mormon guy or girl, be very decent, courteous, and well-mannered. It's like talking to a wall. She has to decide for herself what she believes, but you can definitely help expose her to new ideas.