officer marvin walker got a call for a child not breathing in silver spring. he arrived to find the 19-month-old blue in the face. officer walker performed cpr until the child began breathing again. paramedics arrived and took the baby to the hospital. walker says he doesn't consider himself a hero. >> heard it plenty of times today. i'm a humble person. you know, i had a job to do and -- i did it to my best ability and, you know, thank god that the outcome was good. >> reporter: investigators say that a prescription medicine may have caused the child to stop breathing. the little girl is expected to make a full recovery. >>> a fairfax county man is considered a hero for his fight for our country overseas but it is a victory here at home that is making him glow with pride. the iraq war veteran found out that a promise to his children over a tree house will now be able to become a reality. as derrick ward reports, help came in from down the street and across the country. >> it has automatic the amenities you expect in a tree house. easy access, practical furnis

. >> reporter: montgomery county police officer marvin walker isn't used to a lot of attention. , buta hero -- >> i've heard it plenty of times today. >> reporter: -- it's no surprise when lots of calls come pouring in. >> i'm a humble person. >> reporter: it was a call that led to walker's heroism. it came after 2 p.m. friday afternoon from a frantic mother at a silver spring home. >> a lady said she went to wake up her 19-month-old daughter from a nap and she was unresponsive, not breathing, not moving and was blue around the face. >> reporter: when officer walker arrived, he said the mother led him to a back bedroom where he found the baby girl lying on her back. he knew right away had he to act fast to save her life. >> tried to saying this her a little, no response. immediately i just went to life saving mode, started cpr on the child, made sure she wasn't choking and compressions and rescue breathing. >> reporter: the life saving cpr measures went on for what might have been five minutes but he says it felt like forever. he said had he to stay call and focused -- he said he had