Final answer:
Pedigree analysis cannot show the genotypes of parents or children in hemophilia unless the trait is expressed. Hemophilia is X-linked recessive, making it more common in males, and carrier status in females is hard to identify without phenotypic expression of the trait.
Step-by-step explanation:
Hemophilia is an X-linked recessive trait in humans. If phenotypically normal parents have children without hemophilia, pedigree analysis would not be able to show the exact genotypes of the parents or children.
Sex-linked traits such as hemophilia are more common in males because they require only one mutated X chromosome to be affected by the trait. Females need two mutated X chromosomes to express the trait because they have two X chromosomes. Therefore, a female must inherit two copies of the hemophilia gene, one from each parent, to be affected, making the condition rarer in females. Males are XY and will be affected if their single X chromosome carries the mutation.
As for carrier status, if a mother is a carrier of the hemophilia gene, she can pass the gene to her sons making them hemophilic, and to her daughters making them carriers. However, this carrier status is often not phenotypically visible. Hence, without manifestation of the traits, it is difficult to determine the carrier status of individuals just by analysis of the pedigree unless hemophilia is expressed.