The Burnell children are gifted an elaborate dollhouse by a friend of the family who once stayed with them. They immediately fall in love with the dollhouse, and Kezia especially enjoys the little lamp which sits on one of its tables. When they next go to school, the Burnell children brag left and right about the dollhouse, and they get their entire class's attention. They are allowed to bring any two classmates per day by the house to look at the dollhouse, but they cannot bring the Kelvey children, who come from a family so poor even their teacher treats them differently. Kezia disobeys this rule, and brings the Kelveys by to look at the dollhouse, but she is discovered by her aunt, and the Kelveys are quickly shooed away
The Meaning of this is that its a poem and the meaning is the sun would always shine.
Answer: The author might be suggesting that the bacteria and diseases from the cesspool are leaking into their water source and into the shared water pump water, spreading the disease.