Someone born in '38, could have gotten the polio vaccine, when it came out. Not saying your parent did, but it was possible.
Your parents NEVER had any of the "normal" childhood diseases? REALLY? Did they both live in very isolated places when growing up?
And FYI..........the parent born in '38 would have gotten vaccines for whopping cough and smallpox. Both were around back then and proof of a smallpox vaccination were, as far as I know, requirement to enter school, as far back as the early 1920s, if not earlier, so the parent born in '29, would have also gotten one.
Maybe they did but there were never long term health consequences. I know my mom told me her 2 best friends got polio but even thought she was around them she never got it. Her mother did use herbal medicine and limited sugar which apparently had a profound affect on polio cases. Neither of my parents where "isolated" If you don't have young kids you don't understand the huge push to jab your kid with ever imaginable "vaccination" Also the difference is that lots of kids are wear housed in "daycares" and have constant colds yet have to be vaccinated on almost a monthly schedule. Their poor immune systems are overwhelmed