The place to start might be with a death cert. This will show the date, and cause of death. Once you have the exact date it will be easier to search newspapers for further details.
This looks like a possible match from the BMD Index :
Name: Barbara Berry
Registration district: Wexford
Event type: Death
Quarter and year: Jul - Sep 1916
Age: 30 (est. year of birth 1886)
Volume: 4 / Page: 459
I dont think any historic Wexford papers are available online at the moment, and your profile doesn't say where you are located.. but the National Library in Dublin has a good collection of newspapers, and Wexford town library also has local newspapers..
see :
Local Studies Service, Newspapers for details on ordering a death certs, and the details included see :
Ordering Certs from GRO Roscommon Details included on a Death CertShane