A witch that steals children is commonly known as a child-stealing witch or child-snatching witch. Folklore and mythology from various cultures depict such witches as malicious beings who abduct children for various nefarious reasons.
The Witch (an octopus)
A person who steals is called a thief.
A person who steals is commonly referred to as a thief or a robber.
It is called theft or embezzlement when someone steals money from another person.
A person who steals agricultural produce is typically called a "crop thief" or a "produce thief."
The mythical creature that steals things is called a "Kobold."
it is one of the 16 purnas (stories ) witch have morals
A duck that steals could humorously be called a "robber ducky." This play on words combines the concept of a "robber" with the classic children's toy "rubber ducky." It's a fun and lighthearted way to describe a mischievous duck!
Pirates?
There was a television series in the 90s called "Worst Witch" about a school for witches. Also, there is of course Sabrina the Teenage Witch, which was both a live action series and a kid's cartoon.
The man who takes in the children in "The Lion, the Witch, and the Wardrobe" is known as Professor Kirke, or simply referred to as the Professor. He provides a safe haven for the children at his country estate, known as the Professor's house.
Befana delivers gifts to children in Italy on Epiphany Eve.