Bregor

The published Silmarillion only shows the sons and grandsons of Boromir, but according to the extended genealogy in volume 11 of The History of Middle-earth, he also had two daughters and three granddaughters. Of these, two were important in their own right, though they don't appear in any definitely canonical sources. Andreth played a role in the philosphical dialogue known as Athrabeth Finrod ah Andreth, while Bregil was the grandmother of the hapless Brandir of Brethil.