Maureen Tripp

When the miles get tough, Tripp's thoughts will turn to her adopted daughter Libby, a 5-year-old born in China with Hepatitis B.

A casual runner who is participating in the Marathon for the American Liver Foundation, Tripp said she would be inspired to see her daughter along the course, but hopes her Libby doesn't see her struggling.

''I'm not an attractive runner," Tripp said with a chuckle. ''I might scare her."

Tripp, 53, has a second motivation for running Boston -- 3-year-old Xi Le. Tripp plans to travel to China next month to bring home her second adopted daughter, also born with Hepatitis B. Tripp said she and her husband wanted Libby to have a younger sister, and thought they were the right family to raise Xi Le.

Tripp is confident she will meet Libby in Copley Square, eventually.

''Hopefully after finishing I can regroup a bit before I see her," she said.