what is the reason mr collins gives in his letter for visiting the bennets?

We first hear of Mr. Collins when Mr. Bennet tells his wife that his cousin will be visiting them. Mr. Bennet reads them a letter sent to him from Mr. Collins where Collins speaks of making amends for any past disagreements between his father and Mr. Bennet. It seems that prior to the novel, Mr. Bennet and his brother had a falling out. In his letter, Mr. Collins readily assumes that his overtures of peace will be gratefully accepted and presumes upon the family to announce that he will come stay with them for a week.