Q: Why do I get phone calls on iPhone and iPad?

Check Settings > Phone > Calls on Other Devices on the iPhone(s).

Also check Settings > Messages > Text Message Forwarding

Additionally, you and your wife should use separate Apple IDs.

Use Continuity to connect your iPhone, iPad, iPod touch, and Mac - Apple Support

Link your iPhone number and Apple ID to use iMessage and FaceTime - Apple Support

This occurs when you share the same Apple id.

On all devices - settings - message - Send & receive -remove or uncheck the apple id.  Do the same for start a new convo.

Also do the same for facetime settings.

Then go to settings -phone - calls on other devices - off

Go to http://appleid.apple.com/  and choose Create a new ID.