Robert Flowers never questioned running in Monday's Boston Marathon, even after twin bombings killed three people and injured more than 260 during the 2013 race.

"For most runners, this is the biggest race they run," Flowers, 55, said. "Sure it will be different this year because of last year. Some will be running with raw emotion."

Flowers will be joined by 11 other Darien runners and 36,000 participants from around the world. Four of the 11 Darienites who ran in 2013 are returning to the marathon.

The Boston Athletic Association, the race organizer, increased the field size from 27,000 runners to 36,000 runners following last year's race, according to the marathon website.

"This change was part of our response to the acts that took place in April," the website states. "Our city, our state, our nation and our sport are uniting to show that we don't give in to such things and that we honor those who were most affected by it."

In 2013, Flowers and his wife, Avery, walked into the Lenox Hotel -- sandwiched between the explosion sites -- after Flowers finished the race in 3:25:37 -- a qualifying time for the 2014 race. They were having a drink and food when they heard the first blast, which exploded at the finish line.

A SWAT team swarmed the hotel lobby and evacuated everyone. The hotel would become a command center in the days that followed while a citywide manhunt for the bombers was conducted. In the days following the bombings, Dzhokhar Tsarnaev and his older brother, Tamerlan, were identified as the bombers. Tamerlan was killed during a shootout with police and Dzhokhar, 20, has pleaded not guilty to a 30-count federal indictment that carries the possibility of the death penalty.

Flowers and his wife only had $20 to $40 between them. No wallet. No purse. And one cellphone with a dying battery. Luckily, one of Flowers' cousins lived nearby.

This year, Robert and Avery Flowers have an added purpose for running the race: Raising funds for A Better Chance Darien.

Avery -- who Robert said is not "really a runner" but his greatest support and trainer --has been involved in ABC Darien for years.

Through an email campaign and reaching out to friends, the two have raised more than half of their $10,000 goal for ABC, which is undergoing a capital campaign for a new residence in town.

"We are so fortunate to have the Flowers family so dedicated to our mission," said Jane Yezzi, an ABC Darien co-president. "Avery is a past board president and current capital campaign member, and Rob is running his second marathon in support of ABC."

ABC Darien's goal is to provide young girls from inner cities the opportunity to attend Darien High School and prepare for college. The organization is looking to raise $500,000 to renovate the house at 103 Tokeneke Road and provide a home for more girls attending DHS. The previous home was only able to accommodate six students, while the new house can fit eight.; 203-330-6583; @Meg_DarienNews