As many as 30 churches in St. Louis are being encouraged to provide mentors for children of parents in prison. The program is being led by the Big Brothers-Big Sisters. It hopes to have mentors for about 300 children by a year from now. The program would be patterned after one in Philadelphia. The president of the Big Brothers-Big Sisters organzation for Eastern Missouri estimates there are at least 13,000 children of imprisoned parents in St. Louis and St. Louis County.