A class action lawsuit has been filed against Fisher-Price over its Rock 'N Play sleeper. The suit claims the toymaker knew about the risks to infants, but sold the product anyway. The sleeper has been linked to the death of more than 30 babies over a 10-year period. The American Academy of Pediatrics urged Fisher-Price and the CPSC to recall the sleepers, calling them “deadly.” Fisher-Price said that it stood by the safety of its products and said it issued the voluntary recall “due to reported incidents in which the product was used contrary to the safety warnings and instructions.” The recall covers about 4.7 million sleepers, which sold for between $40 and $149 since 2009.