The air conditioner technician arrived at the Baytown, Texas, mobile home as the medical examiner was removing the bodies. Ramona and Monway Ison’s air conditioner had broken earlier in the week, but the retired couple living on a fixed income couldn’t afford the $1,600 repair. It took three days for Ramona Ison, 71, to secure a loan from the credit union by putting her car up as collateral. The money came too late. The pair were found dead, along with their terrier, Belle, in mid-June, just days into what has since become a two-month-long heat wave in the Southwest with...