Sons of two different fathers and a mother

The story takes place during the Nazi period in Germany, where a German mother and her son live next door to a Jewish family, and the two children are of similar age, often practicing playing the piano together and often playing together. The seemingly harmonious picture was destroyed by the arrival of the German army, informing the Jewish family that they were going to the concentration camp tomorrow. The Jewish parent told the child that he would take him to the toy island, and the child told his little playmate about it, and the child asked to take him with him. The next day the German mother found that her child was missing, she went to the station to find her child, when she opened the door, she found that it was not her own child, it was the neighbors with their sons, the German mother's move she called her child's name and put her hand to the Jewish child, the German mother finally succeeded in bringing the Jewish child home, found that her child also returned home, it turned out that the Jews found that the child followed them and told the German army that it was not their child, pushed the child off the car, and he returned home safely. One kind heart saved two children.