Final answer:
Inkling returned to Ethan's house with a picture of the 'Pudding Thieves,' adding a key piece to solving the mystery in their adventure.
Step-by-step explanation:
When Inkling returned to Ethan's house, he showed them all the picture of the 'Pudding Thieves' he had found, which was instrumental in solving the mystery Ethan was trying to figure out.
The discovery of this picture leads to a series of events that are pivotal in the resolution of their adventure.
In the broader context of the story, Inkling helps Ethan to deal with his struggles by providing companionship and assistance.