Vulgar, kindly, and cheerful, Mrs. Jennings is the widow of a man "who had got all his money in a low way." With both daughters married off, she likes to visit them in their country houses and enjoys the society of their young guests. She is fond of young people and has an eagle eye for their romances — even questioning a servant to find out where Marianne went with Willoughby on the day of the picnic. An inveterate gossip, she passes on scandal about Colonel Brandon even though she likes and respects him.
Mrs. Jennings has much common sense and easily sees through affectation. Lady Middleton may think Fanny Dashwood a charming woman, but to Mrs. Jennings "she appeared nothing more than a little, proud-looking woman of uncordial address." And when John Dashwood blames Edward for keeping his word to Lucy, Mrs. Jennings stoutly declares that Edward has acted like an honest man and that Lucy is a good girl who deserves a worthy husband.
Mrs. Jennings is kindness itself to Elinor and Marianne. She is thoughtful, generous, and solicitous for their comfort and, on the journey to London, does not even seem to notice Marianne's rudeness. When Marianne falls ill, she remains at Cleveland to help Elinor care for her.
A devoted mother, she fusses happily over Charlotte and her first baby. When Charlotte imagines the baby to be ill, Mrs. Jennings shows her common sense, diagnosing the trouble as "nothing in the world but red-gum."
All in all, as Austen says, Mrs. Jennings "was a very cheerful, agreeable woman," probably the most lovable character in the novel.