Incorrect Username

In settings on my son's phone when you select "Family" the attached screen shot appears. My son's account has the name "Mum (Me)" and then "Mum" for my wife is listed below. The weird thing is the photo is the same for both of them. When I look at the family group on my phone it appears as it should and wife's account has the correct photo.

My son's phone used to be my wife's but I did the full factory reset and disconnected AppleID, his phone synchs to his apple watch as you would expect.

Any ideas appreciated - thanks!