Hi Misty,
I've never heard of the vitamins you have your kiddos on. Are they prescribed by your doctor? If they are over the counter, you will want to switch to a vitamin prescribed by your CF doc. They need to be fat soluble in order to be digested properly by CFers.
Andrew is on Vitamax, which we order through CF Services Pharmacey. We order the grape chewables and he likes them. They are a bit sour, but he's used to them. Wayyyy better than the liquid ADEKS he took as a baby!