Simplify the following text for a Grade 6 native English-speaking person.
Original: During the 1945 World Series , a man by the name of Vasili `` Billy Goat '' Sianis attended Game 4 of the series with his pet goat .
Simplified: In Game 4 of the Series , the Curse of the Billy Goat was allegedly laid upon the Cubs when P.K. Wrigley ejected Billy Sianis , who had come to Game 4 with two box seat tickets , one for him and one for his goat .