The parents of a 1-year-old boy allegedly sickened by tainted milk powder filed a lawsuit against the manufacturer, according to state media, in what appears to be the first challenge to official efforts to keep the scandal out of China's courts...The suit was filed last week against dairy company Shijiazhuang Sanlu Group Co., but has yet to be accepted by the court. As is common in China, the filing isn't publicly available. Sanlu's officials couldn't be reached for comment...The family's attorneys, Zhang Xingkuan...said they are seeking compensation of 150,000 yuan ($21,900) to cover hospital fees, travel expenses, time off from work and other costs. The attorney said that the parents claim the boy developed kidney stones from drinking Sanlu...The Sanlu lawsuit comes as some lawyers who offered to assist families of sickened children report being pressured to stay away from the issue...[Also refers to Unilever, Ezaki Glico Co. of Japan, Tian Le Yuan Foods, Kraft Foods]