Can someone please answer this genetics Q and show me the punnet square?

Question

There is a father and mother who have three children: one is a color-blind boy, one is a color-blind girl, and the other is a girl of normal vision. The color-blind condition is X-linked and recessive. What are the genotypes of the three children? What are the genotypes AND phenotypes of the mother and father?  Thank you.

Anonymous · Accepted Answer

Let's say X' is affected by color bind. 

Let's look at 3 children's genotype
Child A: X'Y (he's colorblind)
Child B: X'X' (both of her allele is affected because she's color blind)
Child C: X' X (Because if you look at Child B, she receives X' from mother and X' from father. Child C still receives X' from father but X from mother so she is not affected)

Now let's look at their parents
Their X' comes from mother because boy gets X' from mother and Y from father. 
Look at Child B. Both of them are affected. She gets X' from mother and X' from father.

Genotype
Father: X'Y
Mother: X X'

Phenotype: 
Father: color blind male
Mother: Normal female

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Can someone please answer this genetics Q and show me the punnet square?

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