My parents thought we were exaggerating for sure in regards to our son's behavior issues, until they kept the kids for a week while we were out of country. Upon arriving home I got the whole "wow, I think something's up with DS!" Gee, you think so??
DH was not on board with the dyslexia concerns until he started reading the beginning BOB books with DS. The school asked us to work with him at home and I was the one doing it. He did it once and was convinced something is not right. The repeated struggle with simple sight words like "the", "is" and "and" is so noticeable. Plus, he has reversals, inversions and transpositions like crazy.
Slide 24 at this link seems about right given the stuff he comes up with while trying to sound words out.
http://neurolearning.com/ReadSpellWrite3slides.pdf