Growing Up Without Him

Many know Haymitch Abernathy as an only child but what if I told you he wasn't. Here is my theory about his family and the only one in his family whom wasn't killed. Haymitch had a little sister and here is how life between the two were many may know her as Mrs. Everdeen but to her family she was Ms. Abernathy. Why was she untouched unlike her parents? Why did she never tell her girls of their uncle? Will Katniss and Prim ever find out they have an uncle? What does Haymitch think of his sisters life? Why was Haymitch never there for her? Why??