Kai Chase told jurors that the King of Pop was a hands-on father who often played with his kids Prince, 16, Paris, 15, and Blanket,11, the Courier Mail reported.
She spoke about an April birthday party which Michael arranged for his only daughter, Paris, where he hired a private circus for his kids.
She said that the Cirque du Soleil-style show had men performing on stilts and a woman performing in a giant balloon.
Paris, who was turning 11, and Chase also decorated a room with posters and images of Michael and also played his music throughout the party.
Chase said that the birthday was the last birthday that Paris celebrated.