Huh…   Well, okay, kind of makes sense, excepting big factors of genes and sickness affecting growth spurts, I can think of?  Or birth order, as the eldest wouldn't have any siblings (at the moment) to affect that factor?  Always found deductions of lifestyle/habits/work/etc based on appearance to be really really neat, but kinda wonder about this one.  What would say about an average-looking woman of 5'4", then?

Welcome to the forum!

I have just been proven woefully wrong in my deduction skills...so I think I'm retiring to a shed in the wilderness!

I would say probably not. I study physical anthropology, I've taken several classes on human growth and development. About 85% of stature is genetic, the other fifteen percent is left to outside factors such as illness during times of growth. studies have shown that there is no real difference in height between those breast fed and those formula fed as an infant. by about six months babies who are formula fed tend to catch up to their breastfed counterparts, and breastfed babies have a tendency to grow less quickly once they've started weaning (around 10 months in most western civilizations). There's also what's known as canalization, so if a stressful event occurs (illness, malnutrition, etc.), growth speeds up once they're healthier, to put them back into their growth trajectory. Breastfeeding mothers also benefit from lactational amenorrhea which supresses ovulation making it more difficult to get pregnant while breastfeeding. In conclusion, number of siblings should have no affect on height based solely on the breastfeeding hypothesis. However, there could be a correlation because of other factors. 

Both my kids were breast fed til age 1 and are both giants!