Warin de Raleigh is well documented, as are Ralph le Boteler and his wife Matilda Pantulf. So it's not surprising to see that Ralph and Matilda had a daughter Joanne, born, say, 1253, who married Warin.
Except that the best sources for Joanne, who appears all over the internet, appear to be Marlin Lewis, who cites someone's research, and Geni. And that's not persuasive.
Ralph and Matilda's son William is written up by Richardson, who does not mention a sister Joanna. Richardson notes Warin's children, but does not mention that they had a mother named Joanna.
Can anyone find any records showing Joanna actually existed?