Puddocky is an old German tale. A variation on the tale is The White Cat, written by Marie-Catherine d'Aulnoy in 1698, and Cherry, collected by the Brothers Grimm in the nineteenth century.
Some variants open with the heroine, who is so greedy for one type of food — cherries in Cherry and parsley in Puddocky — that her mother steals it for her. In Puddocky, this is from a witch who demands her daughter, as in Rapunzel. The girl is seen by three princes, and because of her beauty, they quarrel over her. The witch curses the girl for the commotion, turning her into a frog.
The king wishes to know which son will best follow him, and so he sends them to find them a specific piece of cloth (a beautiful carpet, a linen piece fine enough to go through a golden ring, etc.). The youngest son sets out with the least and finds a frog who offers him cloth. It exceeds his brothers' discoveries. The king then sends them out to find either a dog that could fit in a walnut shell, or an excellent gold ring. Again, the frog provides.
For the third task, the king orders them to return with a bride. The frog either transforms another frog into a maiden, or herself goes with him and turns into a beautiful bride. His father selects his youngest son and the frog princess marries him. In the variants opening with the quarrel, the prince recognizes her as the beautiful woman over whom he had quarreled with his brothers.
This story is closely related to The Frog Princess, wherein a transformed frog, the bride of the youngest son, performs better at three tasks to test the brides than the other sons' human brides.
Madame d'Aulnoy began with tasks, and wrought the tale into a highly ornate and literary story. Her king sets the tasks to his sons to distract them, for fear that he will lose his throne. The prince finds not a frog in a dreary swamp but a fanciful and enchanted castle inhabited by cats, and his sojourn there is richly detailed. The cat does not transform merely because the prince needs a bride, but like the fox in The Golden Bird, asks the prince to cut off her head. The cat tells an elaborate story to explain her transformation: After her mother promised her, before she was born, in return for fairy fruit, the fairies raised her, again using the motif as in Rapunzel. When she fell in love with a human king while they were arranging her marriage to an ugly fairy king, they killed her lover and transformed her into a cat. Instead of the youngest son receiving his father's kingdom, his wife bestowed a kingdom on his father, and one on each of his brothers, and at that, she and he still had three kingdoms to reign over.