Anime where a teenage heiress runs off with a famous thief, probably set during Industrial Revolution

Question

I am looking for an anime I saw some years back in which a young teenage heiress, who is being slowly murdered by her guardians, runs off with a world-famous thief. The story was probably set somewhere during the industrial revolution, because the thief had a dirigible that he and his crew used to travel. The girl is kind of adapted by the thief and his crew, and starts becoming one of them.

Also, as far as I can recall, there were no supernatural beings/powers in the story, though I am not very confident about it.

Answer 1

OK, found it after some searching. It's called "Chiko, Heiress of the Phantom Thief" aka "The Daughter of Twenty Faces".

Chizuko Mikamo is a young girl living with her aunt and uncle after her parents died. She behaves coldly toward them, despite their efforts to make her happy, because she knows that they are trying to slowly poison her so that they can take her inheritance for themselves. Because of her intelligence and knowledge gained from reading detective novels, she works to avoid eating the food her aunt prepares, but it is impossible to avoid all together and she still takes in enough to cause her to collapse. Her butler is revealed to actually be the world-famous thief Twenty Faces, who was there to steal Chizuko's rightful inheritance, a family heirloom gem known as the Anastasia Ruby. When he realizes just what Chizuko's been going through, however, he asks her if she wants to come with him and his band on their travels around the world. She agrees and Twenty Faces takes her back with him to join his gang, who affectionately shorten her name to Chiko. Two years pass and Chiko is now a strong thief, having learned the tricks of the trade from Twenty Faces and the members of his band. Now, with Twenty Faces and the rest of the band as her family, she has found a home at last.

Answer 2

Could it be "Scrapped Princess"?

Answer 3

I think it's the daughter of twenty faces where a little girl is being fed poison by her guardians. One day, twenty faces, a super thief that is never caught comes to her "house" and they flee together...