A couple has two children, both of whom have been diagnosed with cystic fibrosis, an autosomal recessive condition. They are expecting their third child and are concerned about the possibility of cystic fibrosis in their baby. They seek information from a genetic counselor. After discussing their family histories, the counselor said that they are both carriers of this recessive condition. What is the chance that the third child of the couple will be free of the condition?