The newspaper articles said aged 36, which seems a bit way out if he was born 1928. And Donald was on stage in the mid-1940s. No indication he was a child actor.
The Lilian Creswell he is living with before and after Cornwall is Lilian Mary Cresswell, 1895-1975 whose death is also registered as Leila Forde (her acting and play writing name) and Leila Cresswell. As with Donald no trace of her before 1940s though I believe she is the Leila Cresswell on 1939 Register born 1905 though with same birthday of 12 February. -original entry says Lilian Forde, crossed out and Lilian Cresswell added, as well as Leila. I say Lilian Cresswell though the black line hiding the line above partially hides what I assume to be Lilian. Register says she is single, but may be her status as the time. No idea of her origin/ maiden name - could be Forde? And what relation is she to Donald. Married, though with a 20 year age difference? Mother? or other relation.
I suppose it possible that the 1916 birth was outside the UK, somewhere where BMD records are not readily available.
Ah, Elfrieda Pullen is opening a new line. According to a family tree she was born Lilian Elfrieda Ruth Mary Pullen 23 September 1919 to James William Pullen and his wife Lilian Mary, nee Lewis who according to a family tree has the same dates as Lilian Cresswell!
You may have found her but I need to do some work here.
Thanks
John