Piper Peadar Broe was, according to information available on line ( https://ronanbrownemusic.com/780-2/peadar-broe/ ), born in 1928. So that gives you a rough idea of her age. I tried a couple of search parameters for the 1911 census, but didn't get anyone (I thought I would get multiple possibilities, maybe I should have tried "Theresa" with an "h", or McCormack minus an "a") Séamus Mac Fheorais wrote a bit awkwardly that she was "an accomplished harpist in the 1930s and 40s.

Have you tried enquiring of any of these organisations?

The Historical Harp Society
https://www.irishharp.org/

Harp Ireland
https://www.harpireland.ie/

Cairde na Cruite
https://www.cairdenacruite.com/

ITMA, Irish Traditional Music Archives
(not only a search, a direct query)
https://www.itma.ie/

Na Piobairí Uilleann
https://pipers.ie/