Wm Riley/Annie Elwood - Census records?

Looking for anyone who might have access to 1900 & 1910 Census records or San Diego City Directory entries of William Riley and his wife Annie Elwood. They had a son Edward William born on 26 April 1900 according to San Diego County Recorders office. Yet my wife's father Gerald Antonio Riley is shown as the son born on that date with the same parents on Gerald's death certificate. Looking for evidence of a second(perhaps twin) son and birth places of William and Annie. Any help appreciated to solve this mystery and try to find earlier records of William and Annie.