No. The Peverells are related to the Potters (as the cloak was passed though the generations though the last living Peverell) and Rowling has said that Harry (The last living Potter) is not related to Gryffindor or Slytherin. Ergo, The Peverells are not related to Gryffindor.
There is no Ron Grigsby but there is a Ron Weasley
they are the same people
Arthur Weasley.
Arthur Weasley
Ron is short for Ronald, which is Ronald Weasley's real name, as shown in The Will of Albus Dumbledore in Harry Potter and the Deathly Hallows and said many times by Hermione Granger in the films.
The Slytherin-related horcrux was Salazar Slytherin's locket, which Ron Weasley destroyed using the Sword of Gryffindor.
Ron Weasley stabbed it with the sword of Godric Gryffindor.
Yes, they are brother and sister.
No
Ron Weasley was created in 1997.
Ron Weasley
Ron Weasley. They have two kids named Rose and Hugo Weasley.
Harry never tell this to any of them, just his son, in the Deathly Hallows's epilogue.
Ron Weasley's owl is named Pigwidgeon, or Pig for short.
There is no Ron Grigsby but there is a Ron Weasley
Ron Weasley was the youngest son and sixth of seven children of Molly and Arthur Weasley
Sorry, but Ron Weasley is fictional.