Continuity mistake: After Amelia grants Casper's wish to be alive (albeit for only a short time), when it cuts to Kat sitting alone at the party, note the distinctive worn chairs beside Kat. In the following shots, those chairs not only move their positions, they also switch places with each other more than once. (01:27:50)
Continuity mistake: When James and Kat first enter Whipstaff Manor, they drop their stuff on the floor. The large suitcase falls over on its side, but it cuts to the overhead wide shot and the suitcase is standing upright (the ghosts didn't do it). (00:19:45)
Answer: It was not Casper (now a ghost of 12 yr old boy) who wrote there was a hidden treasure at Whipstaff Manor. It was Casper's father, Mr. Mcfadden. The treasure in the box is an autographed baseball which used to belong to Casper, before he got sick and died. Mr. McFadden missed his young son Casper, so he invented a machine that can bring a ghost back to life. He considered Casper's baseball a treasure, because to him it is the greatest treasure there is - the baseball that belonged to his 12 yr old son before he died.
Super Grover ★