undedji: afirst i dn't cognizmy frien. it was so embarrassing.reporter: after missing three years, she still has trouble keeping up. bushe does sll have fo years of schooling aad of her, d the chan to ma up forouble all thatrecious me sheost whe in theonvent host: in many parts of the world, the carefree days of childhd include ending war or lake. dthat makes it easy to forget that swimming is not an innate skill. four billion people around the globe are unable to swim -- that's more than half the world's population. drowning is one of the most common causes of accidental death. every minute on average, two people somewhere in the world will drown. reporter: majeda begam treasures her daughter's clothes. one month ago, six-year-old aiyascha drowned near their village. majeda: she was such a good daughter, she was always helping me. everyone loved her. aiyascha would have loved to have had an education. reporter: aiyascha's older sister farjsana is a great comfort to her mother. she misses her sister every day. farjsana: we did everything together