Here's information on how to apply for precheck --- although if you already have a KTN (known traveler number) including members of Global Entry, NEXUS, or SENTRI, need not enroll in the TSA Pre✓® application program.
So if you have a KTN then simply give that information when booking reservations and you should still be up for pre check, although it's not guaranteed that you will be selected. As more and more people become recheck opportunities to be selected may decrease at some airports.
Please let me know if you need anything additional. If not, please rate positive so that I m ay receive credit for assisting you today. Thanks so much :-)
My name is ***** ***** I am happy to assist you. There is no need to apply for TSA Precheck if you have the DoD ID number on the back of your husbands CAC Card and you enter it as the “Known Traveler Number” when making official travel or leisure airline reservations. If you have the military privileges you should have that number still offered to you since he was your husband and are considered a military family.
You can see more here and please let me know if you have further questions and thank you for the service that you and your family gave to our country!
Have a great rest of your week.