Hi, Thanks for writing in. Kidney stones take the same passage out of the body as urine. From the kidney the stones move to the bladder and then through the urethra they are passed out. In your husband, the kidney stones could certainly have been passed out through the penis and urethra. During its passage, the stones might have caused small lacerations or abrasions to the lining of the urethra. This is a sensitive zone and even a tiny laceration can cause significant bleeding. However, the bleeding stops once the wound caused by the stone starts healing. Please make him drink lots of water an pass urine regularly to flush out the system and promote healing.