How older siblings stunt growth

A study is suggesting that having an older brother can stunt the growth of younger siblings. My younger brother’s about a foot taller than me, so it wouldn’t seem to apply to my family. Researchers suggest the trends they observe might be due to uterine factors in second pregnancies, or dilution of time, money or love (see DGR learning outcomes any of you medical students reading this) that parents can invest in children when having more than one.
BBC article.
I’ve got another jab today.