The angelic little tot, who was born on 20 February in New York, can be seen snoozing in the snap which avid social media user Madeleine posted to her Facebook account.
Dressed in a cute blue dress with duck motifs, Leonore is snuggled up on a pillow nestled between party balloons.
"Happy Birthday Grandpa", reads the caption for the image in recognition of the Swedish king's 68th celebration, which fell on 30 April.
Royal fans were delighted with the photo, and are no doubt looking forward to seeing more of Leonore when she is christened on June 8.
Madeleine her husband Chris O'Neill have chosen to baptise their baby daughter Leonore Lilian Maria at Drottningholm Palace Church at 12.00 noon on 8 June 2014 — a year to the day after they tied the knot and two days before Madeleine's 32nd birthday.
Leonore will be baptised in the same gown as King Carl XVI Gustaf, Princess Victoria and her cousin Princess Estelle, whom she met for the first time when Princess Victoria and Prince Daniel visited New York in mid-April.
The baptismal water will be drawn from a source on the island of Öland and the ceremony will be conducted by the same Archbishop who baptised Estelle, Anders Wejryd, assisted by chaplain to the King Lars-Göran Lönnermark and pastor Michael Bjerkhagen.
Princess Leonore, who also has the title the Duchess of Gotland, will have six godparents although they have yet to be named.
Like her cousin Prince Estelle, the little girl will be three months old at her christening.