Today is "do as I say, not as I do" day. Specifically, back up your cellphone.
Since the dawn of the home computer users have been reminded to back up their computer. Only the most virtuous do it, while the rest have had their computers crash, with occasionally horrifying results and have lived to tell the tale, yet are so stricken by the loss that they pinky swear to begin saving our stuff tomorrow. It never happens.
Since we are amongst friends let me ask a personal question. When is the last time you actually dialed a telephone number on your cellphone? You use the stored directory don't you. Do you know every name in that directory? Could you recover every number if you lost your directory?
The SIM card of Mrs. T's ancient phone recently committed suicide, erasing all directories, messages, photos and important life management tools to the ether. She had an easily transferable backup phone, but it sat like a brick until she rekeyed what names and numbers she knew, emailed those people who's names she knew but didn't know how to call, and sat quietly hoping those she had forgotten about would call some day.
Obviously, I don't know how to back your phone up. Some are stored in the clouds of heaven, some can be saved to your unbacked up PC, sometime paper and pencils work. Whatever you need to do, do it, and do your partner's too, if only to spare yourself the grief I've had to deal with.
End of lesson.