A property professional with nearly 20 years experience of estate agency in Suffolk and North Essex. During that time I have carried out market appraisals on over 5000 residential properties and have helped over 1500 people successfully sell their home.
Therefore, a son from a color-blind mother (who receives the trait from his mother on the X-chromosome) will always be color-blind, regardless of the state of the father (who can only give his son a Y-chromosome).
The children of a color vision defective couple (both father and mother) will be color blind. The above pattern is only for red-green color blindness, since the inability to detect blue is caused by a mutation is a gene that does not follow sex-linked inheritance.