This can be unlocked on the 7th level of the game "Partys Over"
From the start of the level follow the dirt path towards the 3 log cabins at the back. Go towards the far left one (one being built).
Remember the following instructions: Between the pool wall and the lodge fence, there is a bush and a group of balloons. Go through the bush and follow the hidden path until you hear music start to play. This will cause your achievement to be unlocked.
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