Pride & Prejudice: After reading I am still wondering how a certain minor

["Letthemeatcakee"]

character is related to the main? The character is Mrs. Annesley, I am not that could in deciphering the old english but from my understanding she is a friend of Darcy's? An aunt? A cousin, perhaps? Please help me clear this up!
If there is no such character in the book please tell me!