>> for pediatric resident natalie stavas, it would be a story of giving back. >> it was a very special day for me. i had decided to raise money for boston medical center pediatrics. >> doctors told chris that this was a day her daughter might not ever live to see. >> they said her prognosis was, you know, maybe she'll be 10 if we were lucky. >> the mitochondrial disease that weakened her cells made her terribly ill. >> those first few years were hard. she needed to have lots of medical procedures, time in the hospital, lots of pneumonias. >> for the kay girls, it had been a tough go. kayla's health challenges, two benign brain tumors for chris, the loss of kayla's father, chris' husband, to a heart attack at age 42. but this would be a joyful day. a day to make history as a mother-daughter, wheelchair team. >> this was the first time in the 117 years with the boston marathon that a female duo team actually entered and was going to complete the race. well, if we're going to start this, we're going to finish it because one shot to do it and we're going to do it. >> natalie, too, had a sp

>> for pediatric resident natalie stavas, it would be a story of giving back. >> it was a very special day for me. i had decided to raise money for boston medical center pediatrics. >> doctors told chris that this was a day her daughter might not ever live to see. >> they said her prognosis was, you know, maybe she'll be 10 if we were lucky. >> the mitochondrial disease that weakened kayla's cells made her terribly ill. >> those first few years were hard, she needed to have medical procedures, time in the hospital, lots of pneumonias. >> for the kay girls, it had been a tough go. kayla's health challenges, two benign brain tumors for chris, the loss of kayla's father, chris' husband to a heart attack at age 42. but this would be a joyful day. a day to make history as a mother-daughter wheelchair team. >> this was the first time in the 117 years of the boston marathon that a female duo team actually entered and was going to complete the race. well, if we're going to start this, we're going to finish it because one shot to do it and we're going to do it. >> natalie, too, had a special ru

natalie stavas was running the race with her father. >> i could immediately sense that something wasbly wrong and chaos broke out almost immediately. they tried to stop us and they were actually trying to barricade the rest of us back. i went over the barricade. police officers were yelling at me, stop, you must stop. and i kept going. finally, as a police officer actually grabbed my arm and he said, ma'am, ma'am, you must stop. and i said, i'm a pediatric physician. i'm a pediatric physician. you have to let me go. you have to. >> dr. stavas sprinted towards the finish line and straight into a war zone. >> the crowd screaming and people screaming in pain and blood has a very distinct smell and you know that you're facing grave, grave tragedy if you -- if you're feeling that and you're sensing that. that you can smell the blood. i went to the next woman who was ahead of me and right in the middle of boylston street and she was laying on her back and i said, let me help you. let me help you. i'm a doctor. she showed me the wound and it was a large wound to the groin. oh, it was a horr

natalie stavas was running the race with her father. >> i could immediately sense that something wasribly wrong and chaos broke out almost immediately. they tried to stop us and they were actually trying to barricade the rest of us back. i leapt over the bar kay, actually. i just went. police officers were yelling at me, stop, you must stop. and i kept going. finally, as a police officer actually grabbed my arm and he said, ma'am, ma'am, you must stop. and i said, i'm a pediatric physician. i'm a pediatric physician. you have to let me go. you have to. >> dr. stavas sprinted towards the finish line and straight into a war zone. >> the crowd screaming and people screaming in pain and blood has a very distinct smell and you know that you're facing grave, grave tragedy if you -- if you're feeling that and you're sensing that. that you can smell the blood. i went to the next woman who was ahead of me and right in the middle of boylston street and she was laying on her back and i said, let me help you. let me help you. i'm a doctor. she showed me the wound and it was a large wound to the