After that, Zhu taught his son to improve his endurance and other basic skills. For example, Zhu made De'en raise his arms perpendicular to his body, he told Beijing Youth Daily.

He hung a water bottle on his son's trumpet and added water to the bottle to increase his son's arm strength. Jump-roping and pushups also helped strengthen the boy's lungs and arms.

When Zhu was training De'en, he often inspired him by telling him to imagine he was using the song to tell the story of the motherland to friends far away.

Over the past two months, De'en practiced the song about a thousand times and was often too tired to speak.

To make sure everything was properly prepared, Zhu also asked his friends to find a special valve oil that could be applied to the trumpet.

"Nearly the whole world would be watching the ceremony, so I needed him to realize the importance of it and try his best," Zhu told Beijing Youth Daily.

He told Beijing News that De'en does not have to be a trumpeter when he grows up, but he can master the instrument no matter his profession.

"When he feels bad, he still can play the trumpet to relieve his mood," he said. "I also hope that more children will grow to like the trumpet and play it."