* Genetics are complex: Hair color and eye color are determined by multiple genes, not just one. Each parent contributes one copy of each gene to their child.
* Recessive genes: Some genes are dominant, meaning they'll express their trait even if the other copy is different. Others are recessive, requiring two copies of the same gene to be expressed.
* Unknown combinations: We don't know the specific genes the parents carry, just their outward appearance. They might carry recessive genes for hair color or eye color that aren't visible in their own phenotype.
To give a more accurate probability, we'd need:
* Family history: Knowing if grandparents or other relatives had red hair or blue eyes can provide clues about the parents' gene combinations.
* Genetic testing: DNA testing could reveal the specific genes each parent carries, allowing for a more accurate calculation of the child's potential traits.
In short, there's no simple answer! Many possibilities exist, and the chances of a child inheriting red hair and blue eyes can vary greatly.