My baby is almost 8 months and is very long. Even though the reviews stated they ran large, it seemed odd to need to buy 3-6 months since she is so tall for her age. Anyway, the 6-12 months came and I was in SHOCK. It looks like it would fit a 2-year-old! It is HUGE. The quality is good enough that I am reordering. Will see if the 3-6 month ones will work.