after surgery i. didn't have a wheelchair. my legs we atrophied behind my back and i walked on my hands all the time. >> reporter: six years later a transv chance visit by an american to the orphanage changed her life. >> i immediately knew she was my mon. >> reporter: adoption gave tatiana an instant family. her mom pushed her to get involved in sports. >> getting involved in sports saved my life. i wrote down goals and said i really want to be a paraathlete. >> reporter: the youngest member of the athens pair liralympic g and in london finally won gold. in 2013, mcfadden won the grand slam title for marathon wheelchair racing and traded it for a sit ski. now she's back in russia where she's competing in the sochi paralympic cross-country nordic skiing event. dr. sanjay gupta, cnn reporting.