I have a lot of info for you...so let me start. First of all, I think that your mother-in-law will be able to be cured of it if she is a healthy individual with no compromising disorders. There are several antibiotics out there for Pseudomonas. And I think that you are right to be concerned with having your child be around her. With your child having CF, he/she is definately more suseptible to this infection. When a person with CF is infected with Pseudomonas, it does not go away...or at least that is how I understand it. It is treated with antibiotics, more often Tobramycin (Tobi) through a nebulizer. And then the infection goes dormant until the person's immune system decompensates or the health is compomised. I am a mother of a 6 y/o with CF...and I am also a nurse. My daughter was first infected with Pseudomonas before the age of one. She was treated with nebulizer Tobi, and the infection went dormant. We saw it again this year in March. So she was good for about 5 years. Again...we did the Tobi, and she is doing beautifully. I hope what I have said helps, and none of my information was wrong, but definately speak with the clinic....they are always reassuring...and I know you will feel better. If you have anymore questions or need to vent, you can e-mail me anytime....mhnurse02@yahoo.com. Good luck to you!!