well we were on alimentum for a while and i wasnt sure if he needed either.. finally when he turned 7 mos. i tried goodstart and than found out quickly it didnt agree with his system, soo we are on soy now with no problems. but he has been so fussy, but i am drumming it up to his two teeth that are popping through! soooo, i guess you will never know till you switch and i am happy that i did because we are saving some money now;) and i know that he cant have foods with dairy yet but he can have soy. sooo , this way you’ll know and hopefully she will keep doing well!