The sister of My 600 Pound Life star Dolly Martinez told cruel trolls to "f- all the way off" after she announced her sibling's death at the age of 30, Wonderwall.com can reveal. Martinez died from congestive heart failure at a Fort Worth, Texas, hospital on April 11. After Lindsey Cooper announced her sister's passing, she received vicious taunts about how her family should have done more to "save" the morbidly obese TLC reality star.