The chapter on correspondence displays personal letters. Among them, the letter of the King of Poland and the Grand Duke of Lithuania, Stanislaw August, offering condolences to Paulina Ogińska on the death of her husband, Andrzej Ogiński, and expressing hope for the promising future of her son Michał Kleofas; the correspondence between parents and children, and between relatives; holiday greetings. These letters unveil the everyday life of the family, concern for the relatives, the financial situation, travels, relations with other individuals important for Lithuanian culture. Many of the letters will be of assistance to researchers in identifying the presence of a family member in some or other location, the place of their residence at different times, or family status. The exhibited letters were written in Rietavas, Zalesye, Memel, Warsaw, Florence, Geneva, Veisiejai, Plungė, Mūro Strėvininkai. This chapter also displays the original of Ogiński‘s “Precepts to a Son”; it also, for a first time, presents 40 letters between Michał Kleofas, his wife Maria and their son Ireneusz. The chronological range of the documents encompasses 1732–1913.