Heather, First I am sorry to hear your baby was sick. I hope she is better. As for levels raising when a child is sick…yes they do. When my son has a cold or fever I take him off his milk and no meat so his levels don’t raise too much. I completely here your concern about freaking out. I cannot tell you how worried I was in the beginning. I did not know that my son would have the tolerance he has today. Every week I would worry that his levels would go too high and I would have to switch to metabolic formula. I never use to buy more than a weeks worth of Similac for fear I wouldn’t be able to use the formula. I had my shares of tears in the beginning but as the weeks went by and he hit milestones I eased up. Your daughter is so young that you truly won’t know her tolerance until she stops this rapid development as a baby. When my son turned one we tried to switch him to regular milk and it didn’t work. Meaning that his levels went about a 5 when he went over 12 oz of milk but 6 months later his levels actually went low (under 2) and now he can tolerate more than 12 oz of milk. Believe me the not knowing how much phe your baby will tolerate drove me crazy. I do promise you in a few months from now as your baby hits those milestones and you get use to the routine your mind will be at ease. One thing to think about is having your baby’s blood drawn to find out what PKU mutations she has. I don’t know if you know what this means or not. Each person with PKU has two mutations, one from the mother and one from the father. Knowing the mutations can give the doctor an idea of how severe the PKU is and potential tolerance. My son has one mild mutation and one moderate one…hence his tolerance. This test costs about $1000 but we were lucky enough that the hospital we go to had money left over last year in their budget and did the test for free. I hope this helps and I do want you to know that this gets easier.