But by the time the triplets turned 10, it was obvious that the Marquards, who live in Orlando, had weight issues. One of the girls, Alexandra—the picky eater—was slender. Audrey and Caroline, however, were "verging on chubby," says Priscilla. Her son, Philipp, was already there; at 14 the boy weighed 260 pounds. Meanwhile, Priscilla, now 42, had her own troubles: After having kids, the former Ford model found that she was carrying an extra ten to 20 pounds that seemed impervious to diets.
While each of us has a special relationship with the scale, in many cases the family factor weighs in (literally). Inheritance plays a part in determining your size, but unlike red hair or blue eyes, DNA doesn't tell the whole story: Psychologists and doctors have found that family dynamics—the way you and your brood interact and relate to one another—can have a major influence on weight.
"We need to change how we look at food, and it all starts with families," says former FDA commissioner David A. Kessler, MD, author of The End of Overeating: Taking Control of the Insatiable American Appetite. Too often, parents offer treats in an attempt to placate children, and the food—chips, sweets—tends to be high in fat, sugar, and salt. These substances set off reward centers in the brain, says Kessler, creating a sense of pleasure and a desire to overeat.