I think she was. I am half Welsh, but I can't stand a South Wales accent. Sorry to Welsh people:( a transatlantic accent is strange, though. Lena Dunham's Girls series had a character with a part Scottish part American accent. it was a bit weird. I don't know what CZJ sounds like now. I would think KJ's children would have the accent of where they are growing up.
Well Carrie was on something for sure.! Not a good look for the show.. she really was a mess.!
As for Katherine Jenkins and her child I am not sure she meant that but was just saying how Catherine slips from one accent to another..?