Welcome back to Ireland Reaching Out!
I assume you have the civil birth record for young Bridget. https://civilrecords.irishgenealogy.ie/churchrecords/images/birth_returns/births_1904/01805/1707214.pdf
She was born December 10th 1904 in the Edenderry Workhouse but likely the medical facility at the workhouse.
I think you have sorted out what happened. It must have been very heartbreaking for your grandmother.