Describe the episode when Virginia is thought to be lost, when she has gone through the tapestry door with the ghost.

In Chapter Five of "The Canterville Ghost," Virginia finds the ghost looking very depressed in the Tapestry Chamber. After a brief conversation, she learns that the ghost is very tired because he has not slept for 300 years, since the night he was starved to death by his brothers-in-law for the murder of his wife. The ghost is desperate to sleep in the Garden of Death, his final resting place, but he must fulfill certain conditions before this is possible.

According to the prophecy written on the window, the ghost can only have eternal rest when a "little child" cries for him and prays with him, so that his sins might be forgiven. Virginia agrees to be this "little child" and, together, they disappear through the tapestry door.  

There are tantalisingly few details about what happens when Virginia passes through the door with the ghost. On her return, in Chapter Six, she simply tells us that the ghost is now dead, having been forgiven by God, and that the ghost has bequeathed her a box of jewels as a reward for her help.

To put this into context, Virginia has fulfilled the prophecy written on the library window and, in doing so, has granted eternal peace to the man who haunted Canterville Chase. She is truly "an angel," as the Duke later describes her.