VERY Skinny Neighbor Dogs?

My neighbors have three dachshunds, two female and one male. With four young children, they don't have much time to pay attention to their dogs. (The dogs have an invisible fence, past the yard and onto the sidewalk, which is very annoying, because they attack you when you walk on the sidewalk!) They are left outside all day and never mind their constant barking! It is starting to get cold and dachshunds don't like the cold, and they are going to FREEZE this winter. Another thing I'm concerned about is how skinny two of them are. The females are VERY skinny and its horrible. I don't know what to do, weve talked to one of the parents, and they just said, "Oh their not malnourished...". Bull. They are sooo skinny. WHAT DO I DO?