C.C.
I transitioned my son to go & grow at 9 months because it was cheaper! It was the same consistency and additional nutrients for his age. He used it until 11 months old when he decided he wanted nothing to do with formula or bottles, so we switched to a sippy cup of whole milk then. My doctor said that the formula companies would love for you to keep your baby on formula for as long as possible, but it's not necessary after their birthday.