Hong-Kong made fourth sequel of "My Life as McDull".

Springfield Kindergarten is desperately in need of money - The principal is behind on the rent, and the electricity is getting cut off. After a fundraising dinner ends in spectacular failure, the music-loving principal decides to form a student choir as last resort. With the help of a shady talent manager named Big M, the Springfield Kindergarten Choir becomes a huge success, and little McDull discovers that a little thickness really can make a great voice.

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Same setting: Mak Dau BoloYao WongZi
Prequel: Mak Dau Xiang Dang Dang
Sequel: Mak Dau wo He wo Mama