How do the colours of the changing blood-stain change the belief of the otis family?

it writes at night

I do not think that it is the changing color of the blood stain that begins to change the Otis family's belief in the ghost. ?I believe it is simply the blood stain itself that causes a change in their beliefs. ?

When the story begins, the Otis family does not believe in the Canterville Ghost at all. ?They think it is completely fabricated. ?

"His body has never been discovered, but his guilty spirit still haunts the Chase. The?blood-stain has been much admired by tourists and others, and cannot be removed."

"That is all nonsense," cried Washington Otis.

Immediately after that line of text, Washington Otis scrubs out the entire blood stain with "Pinkerton's Champion Stain Remover and Paragon Detergent." ? Unfortunately, the blood stain reappears the next morning. ?It appears again after two more scrubs as well. ?At that point, doubt begins to creep into each of the Otis family members. ?

"Mr. Otis began to suspect that he had been too dogmatic in his denial of the existence of ghosts."

During chapter 2, Mr. Otis comes face to face with the ghost himself, and all doubt is removed completely. ?The best part of the Otis family is that none of them are scared of the ghost. ?In fact, the Otis family antagonizes the ghost more than the ghost antagonizes them. ?

The next time that the blood stain is mentioned is at the start of chapter 3. The family has ceased to worry about the blood stain and actually finds it fun to watch it reappear in a variety of different colors. ?

"The chameleon-like colour, also, of the stain excited a good deal of comment. Some mornings it was a dull (almost?Indian) red, then it would be vermilion, then a rich purple, and once when they came down for family prayers, according to the simple rites of the?Free American Reformed Episcopalian Church, they found it a bright emerald-green. These kaleidoscopic changes naturally amused the party very much, and bets on the subject were freely made every evening."?

The color change doesn't affect their belief. ?Their belief has already been changed. ?The color change of the stain is only another source of fun for the Otis family.?

The blood stains were scrubbed and rubbed away by Washington Otis but they reoccurred daily. This repeated occurrence of the blood stain aroused interest among the Otis family. The wonderful changes in its colors and shades really amused them. Every evening the family would have great fun when they made bets about the next shade. The whole thing was funny and none of them was frightened of the stains but they were surprised as to how they reappeared in spite of the door and windows of the library being locked and barred. It was Washington Otis who began believing in the idea of ghost's existence. Mr. Otis also thought of his denial of ghost's existence. Mrs. Otis also expressed the wish of joining the Psychical Society to know about ghosts. Only Virginia did not join the jokes as she knew that the stains were made using colors from her painting box.

When otis family enters the chase bloodstain was the first physical evidence to prove that a murder has been committed & the mansion is haunted. Any attempt to wipe it away leads to a threateningand strange peal of thunder and fainting of Mrs. Umney.Yet, Otis family sticks to their belief that Ghosts don't exists But soon it has changed the mindsets of americans , who don't believe in anything easily, because even after wiping it away and locked the room blood stain was reappearing even sometimes red, deep red, brown, black, and even emrald green.