Hi to all who are following Gertrude.
I don't have much new of consequence, but MonicaL forwarded an Apr 1927 ad that promoted Gertrude & what may have become Gertrude's second husband, Harry Hansen. It specified that Gertrude was a Top C Soprano. Not familiar with that, I asked Mr. Google to help.
It appears that a Top C Soprano may also be referred to as "coloratura", which, when used without further qualification, normally means soprano coloratura.
A coloratura soprano role, most famously typified by the Queen of the Night in Mozart's The Magic Flute, has a high range and requires the singer to execute with great facility elaborate ornamentation and embellishment, including running passages, staccati, and trills. A coloratura soprano has the vocal ability to produce notes above high C (C6) and possesses a tessitura ranging from A4 to A5 or higher (unlike lower sopranos whose tessitura is G4–G5 or lower).
That's my wee find for tonight.
mshrmh, I seriously thinking of order that certificate the library suggested for Gertrude. If you're correct & it includes wife of/widow of + his occupation it may tell me which Harry Hanson she married. (It appears that the theatre Harry died in London in 1972; obit generously provided by Monica.)
I will let you know as other bits unfold.