Iowa Code § 633.222: Biological child — inherit from father.

Unless the child has been adopted, a biological child inherits from the child’s biological father if the evidence proving paternity is available during the father’s lifetime, or if the child has been recognized by the father as his child; but the recognition must have been general and notorious, or in writing. Under such circumstances, if the recognition has been mutual, and the child has not been adopted, the father may inherit from his biological child.