Hi Jennifer -
First of all, thanks for helping this family...we moms need all the help we can get! I'm sure she appreciates it!
Emily is 4 and has been doing "Nose Rinses" for about 4 months now. We do them at least 4 -5 times a week, more if needed. We use the Niel-Med bottle kit.
It was tough for her to do the first few times, but she got the hang of it. We make sure the water is luke warm (We boil disstilled water and let it cool to almost room temp. before using it). We also let Emily help squeeze the bottle so she knows when the "whoosh" is coming. Those two things helped her get over her initial disomfort, I think.
It also helped when her big sister (no cf) started to do sinus rinses, too. It became part of the nightly routine - right before teeth brushing, for both of them. Actually, big sister was a little jealous of all the attention Em was getting and asked for a bottle. It worked out great, since she was getting a cold at that time. I ended up getting one for myself, too, eventually.
Emily is a kid who LOVES the gross out factor, so when we started keeping track of the size of the boogers that got washed out, she loved it. For a while, the girls were crowning themselves Booger Queen for the night!
I think it's important to remember that all new skills take time to develop. Just keep trying it. He'll get the hang of it eventually.
We do have a video of Emily doing her nose rinse that we could e-mail to them if it would be helpful for him to see a kid his age doing it! Let me know. (We took the video to show her ENT who was VERY impressed!)