The first family’s library grew on Saturday after President Barack Obama and his daughters shopped at a local Washington DC bookstore.

Obama, who is the author of three books, made the heavily publicised shopping trip to promote Small Business Saturday – event created in response to the shopping hysteria of Grey Thursday, Black Friday and Cyber Monday.

He, Malia and Sasha strolled the aisles of Politics and Prose, before walking away with books including a bestselling book on medicine, Being Mortal by Atul Gawande ; Jacqueline Woodson’s National Book Award-winning memoir, Brown Girl Dreaming; and Denis Johnson’s post-9/11 novel, The Laughing Monsters.

One shopper took the opportunity to ask Obama to close the Guantánamo Bay detention center. The president said he was working on it.

The Obamas shopped at Politics and Prose last year. Their 2013 stash included books by Carson McCullers, Khaled Hosseini and EL Doctorow.

The White House later provided a full list of Obama’s purchases in support of Small Business Saturday 2014:

• Being Mortal: Medicine and What Matters in the End (Atul Gawande)

• Age of Ambition: Chasing Fortune, Truth and Faith in the New China (Evan Osnos)

• Brown Girl Dreaming (Jacqueline Woodson)

• The Narrow Road to the Deep North (Richard Flanagan)

• The Laughing Monsters (Denis Johnson)

• All the Light We Cannot See (Anthony Doerr)

• Heart of Darkness (Joseph Conrad)

• Nora Webster (Colm Toibin)

• Cartwheeling in Thunderstorms (Katherine Rundell)

• A Barnyard Collection: Click, Clack, Moo and More (Doreen Cronin)

• I Spy Sticker Book and Picture Riddles (Jean Marzollo)

• Nuts to You (Lynn Rae Perkins)

• Junie B Jones and the Stupid Smelly Bus (Barbara Park)

• Junie B Jones and a Little Monkey Business (Barbara Park)

• Redwall (Brian Jacques)

• Mossflower (Brian Jacques)

• Mattimeo (Brian Jacques)