Mystery Art - Can you ID it?

Do you know the name of this painting or who painted it?

I'll share details related to the painting later, but I wanted to see if anyone knew anything about the art as neither I, nor the owner, know anything about it.

It's a charming painting, showing two young children in costumes, the little girl wiping the boy's nose. I've included the actual painting (cropped down) and a darkened version to show the details. I have something special I want to share with readers once I find out more about the painting. Thank you!