Gertrude Lawrence (portrayed by Julie Andrews in a film ?"Star"?) was, of course, Noel Coward's partner in many plays and musicals (Private Lives, Red Peppers etc). There has been a two-hander show "Noel and Gertie" about their relationship touring UK for some time (I saw it in Windsor). Never heard about the wheelchair, though, must have been late in her career. She was a singer, dancer and comic actress.