Her father says Krystle Campbell, of Medford, Mass., had gone with her best friend to take a picture of the friend's boyfriend crossing the finish line on Monday afternoon.
William Campbell says his daughter, who was a restaurant manager in nearby Arlington, was "very caring, very loving person, and was daddy's little girl." He says the loss has devastated the family.
He says the friend was seriously injured in the explosion.
The bombings injuried 176 , 17 of which are critical, and killed three.(Information from the Associated Press was used in this report.)
An 8-year-old, Martin Richard of Boston, also died. He was at the finish line watching the race with his family.