No. They aren't. No, but funnily enough, the Patriot from Agents of SHIELD is Thaddeus' uncle. Betty, Banner's love interest, is named after Mace's wife, also known as the heroine Golden Girl, who was the 1940's comics' version of Peggy Carter (teammate of Steve and Bucky, and Steve's wartime girlfriend).

Is Everett Ross son of Thaddeus Ross?

As far as I know they aren't, but I just found it a little odd they had 2 characters with the same last name in the same movie without any connection. In the comics, no he has no relation to Thunderbolt or Betty Ross.

Is Thaddeus Ross Dead?

The mutant rendered Bruce Banner unconscious without draining him of all his life energy, and then headed towards Betty. ... Telling Betty he had been wrong about Bruce and that he himself loved her, Thaddeus Ross died in his weeping daughter's arms.