Reasoning question, why is the man who opened the door and who is the murderer?

The man didn't die, and the first child didn't come in. He just saw a man lying on the ground outside the window, with a little blood on his head, and did not directly confirm that he was not breathing. Second, these children are playing baseball. They came to this yard to check the ball, which means that the ball was hit. The third window is half-covered, and you can see half a person's body, which shows that the covered seam is not small. Fourth, the dead are greeted by the door, which is the most real, indicating that the person in the photo is not dead.

To sum up, the children played baseball, and the baseball was hit and flew into the window. No sooner had the "dead man" walked through the window than he was hit on the head by a baseball. The "deceased" fell dizzy and his head was bleeding. At this time, the child came to check the ball and saw a man lying on the ground in the window, thinking he was dead, and called the police. After a while, the "dead man" woke up, got up and dried all the blood. Then the police came and asked about it. The "dead man" opened the door and smiled and replied, "Do you believe everything the child says?"