If deflation occurs would you ask for a pay reduction as well? Probably not.

But, at the same time you have to do what's best for you and your family. Easiest thing is just to have a straight up conversation with your manager and see if you can get a timeline for a response and specific actions that will be taken in pursuit of this. Be prepared for "no", and be prepared to have to find a new job. In the vast majority of conversations I have with people on this topic, they have to find a new job to get a higher salary, unfortunately.