At first glance, sophomores Andrea and Alex Costaldo appear to be mirror images of each other, but after one gets to know them, their physical appearance can begin to look as different as their personalities.

Reserved and persistent in reaching her goals of being an entertainer, Andrea, unlike her sister, is homeschooled. Andrea handles a hectic schedule, traveling back and forth from various locations, such as New York and Los Angles to practice dancing, singing and acting.

"Sometimes I expect too much from myself, and sometimes I work and drive myself too much," Andrea said. "My sister is goal oriented as well, and even has time to party."

Her identical twin sister Alex finds time to sketch in preparation for her future career in fashion design.

"My sister loves high fashion and always has to match or she freaks out," Andrea said. "Anytime she walks out of the house, as my father says, ‘she treats it like a runway’."

Studies have shown that though identical twins share 100 percent of their genes, they are not predestined to be similar. The question nature versus nurture comes into the picture. Though they may share the same household, other environmental features, such as friends, can have a great effect.

"I usually just laugh when people mistake us because we have such different personalities," Alex said.

It is hard to imagine what it is like to grow up with someone who not only looks like you but is constantly by your side. Only one in every 285 births in the United States are identical twins.

"It is easier growing up with a sibling because there’s no one in the world who will be there for you like your twin," Andrea said. "You have a friend for life."