Looks like she died between 1920 and 1930. For that info you would have to go to Mass Archives - they have the BMD index for the years 1915-1970 - you could find her death that way and then go right down the street to Mass Vitals and see actual record. I use the index at Archives first because Vitals charges $9 an hour so going to Archives saves a little time but sometimes if you are there(Vitals)less than an hour they won't charge.
Another way to find her death is thru a directory. Sometimes a death of a person is listed on them.
go to www.familysearch.org
next screen scroll down and click on United States
next screen scroll down and click on the state you want - this will narrow down the databases rather than scrolling thru all the states.