Hello Eamonn210,
To clarify, does this issue occur when other people text your wife as well? If so, we suggest that you verify the phone number the is enabled for iMessage, on her iPhone. Here's how:
"Set up your phone number
On your iPhone:
- Go to Settings > Messages and make sure that iMessage is on. You might need to wait a moment for it to activate.
- Tap Send & Receive. If you see “Use your Apple ID for iMessage,” tap it and sign in with the same Apple ID that you use on your Mac, iPad, and iPod touch.

3. In the "You can receive iMessages to and Reply From" section, make sure that your phone number and Apple ID are selected.
4. Go to Settings > FaceTime and make sure that your phone number and Apple ID are selected in the "You can be reached by FaceTime at" section.
On your other devices, you can now turn on the phone number that you just set up:
If you use this feature and share your Apple ID with someone, you can't prevent them from seeing your conversations. Instead of using the same Apple ID as someone else, set up Family Sharing.
Remove your phone number
If you don't want calls or messages for your iPhone on your iPad, iPod touch, or Mac, you can remove your phone number. There are two ways to do this:
- On your iPhone, go to Settings > Messages > Send & Receive. Select your Apple ID at the bottom of the screen and tap Sign Out. Then go to Settings > FaceTime, select your Apple ID and tap Sign Out.
- If the phone number that you want to remove belongs to an iPhone that you can't access, change your Apple ID password. This removes all phone numbers from your iPad, iPod touch, and Mac. Calls or messages for the removed numbers won't appear on those devices anymore."
More details here: Add or remove your phone number in Messages or FaceTime
Let us know if this helps.
Cheers