Kristine Cathrine Ploug (1760–1837), known as Aunt Ploug, was a relative of playwright Henrik Ibsen, cited as the influence of some of the characters in his plays, such as The Rat-Wife in Little Eyolf. She was a sister of Johan Andreas Altenburg, Ibsen's maternal grandfather, and as such the aunt of Marichen Altenburg and great-aunt of Henrik Ibsen. She lived with her brother from around 1799, following the death of her husband, and after Johan Andreas Altenburg's death, she lived with the Ibsen family. She died at Venstøp in 1837.