"Father day by day"   01     Cory Petersen's daughter, Lilly, was born five weeks ago. "I didn't imagine how beautiful it was to have a baby until I had Lilly," Cory said. At the age of 19, Cory's new life as a father is about to begin.       02     Cory is a full-time worker for a local garage as the youngest mechanic in the shop. His co-workers nicknamed him the "exhaust pipe specialist."       03     "Sometime I feel that I have two children: Lilly and Cory," his wife Nicole Petersen said with a laugh.       04     A baby stroller is always on the bed of his pick-up truck wherever the family goes out. Cory is struggling to put it together at a Wal-Mart parking lot.       05     Cory has a passion for gardening in his backyard. He always stops by the agrochemical section in the hardware shop. "It's fun to improve my garden for my family," Cory said.       06     As a father, it is a new responsibility for Cory to attend the Baby Parade, a monthly event at the church where his family goes every Sunday.       07     Cory wants to make his family happy by providing them with his home-grown vegetables. "These lights are not supposed to be used for gardening," Cory said with a laugh. Lights are the trademarks of his pick-up truck, which he has been passionately working on "pimping out."       08     TV programs and movies usually end the Petersen's nights. Instead of staying up late watching his favorite MTV programs as he was doing before, Cory goes to bed earlier these days.