The Brass Lantern

The Brass Lantern is a local restaurant in Megaton run by the Stahl family. Jenny Stahl can be seen serving local settlers outside. Leo Stahl works inside the restaurant. Andy Stahl is the owner.

They are siblings. Leo is the oldest (as mentioned by Jenny if you ask her about your father). After the death of their parents Leo Stahl took charge of raising his younger siblings.

Loot
If you don't mind taking a karma hit, there's an easy terminal in the back belonging to Andy Stahl that has notes on it about missing inventory as well as the option to open a floor safe. That floor safe is next to the terminal and has 300 caps in it.

Story
The Chinese neon sign reads "明家快", (Mingjia Kuai[can]); the fourth character 餐 (can) is missing. Mingjia is a sinification of "Megaton" that literally means "house of brilliance", and the sign means "Megaton Fast Food".