This is not the right way to use/share Apple ID.
1. You can share purchases using the purchasing Apple ID in Settings > iTunes & App Store > Apple ID: > here.
Note: Recommended in a household so no need to re-purchase apps, movies, books and music.
2. Settings > iCloud > Account > Apple ID here > Find My iPhone: ON
Note: If each of you have their own Apple ID, each will have 5GB free, otherwise all will be using this same 5GB.
You can use the same (complex) passoword even if you are using a different Apple ID so no big deal to use their own Apple ID for FMiP.