Fall & Winter Wardrobe

My daughter is in some 3-6m clothes and 6-9m clothes. 6-9m is kinda big on her right now. I honestly don’t know what size to get her fall and winter clothes. My husband said 12m but wouldn’t that be way too big. I plan on getting some stuff at the end of this month because Carters coupons lol. I could get some 9m stuff and some 12m stuff. What would you get?