From what I've heard, it is good to hold off on food as long as possible. But it sounds like to me that Kaylee isn't filling up on just bottles. My question to you is...is she strictly on breast milk or are you supplementing with formula?
If she is still on breast milk, try supplementing with formula first. But if she is formula fed and if she seems hungry and her bottles aren't satisfying her like they used to, then it is probably time to introduce rice cereal into her diet. I would start with adding one tsp of ceareal once a day either in her bottle or spoon and see how she tolerates it. Then go from there.
My son,who is now 15 months, started cereal at about 4 months. He had bad reflux, so it helped keep the bottles down. He, unlike my daughter, was ready for real food at an early age--we started him on solids not too long after the cereal because he was just starving.
My daughter, who is now 3 yrs, didn't have an interest in anything but the bottle until about 7 months so we started her on solids after 8 months. Neither one of my children have food allergies (that are known) and they are very very very good eaters.
I would advise you to consult your pediatrician. He can give you more tips and advice on how and how much cereal to introduce to your baby.
I hope this helps. If I can help any more. Please let me know!