Dear Frank and Mary
The revelation I have about this matter, though I am not sure whether it makes sense but I believe what the Holy Spirit has revealed is always right.
When I check the temple where Moses was a High Priest, there was always blood and water, which water was used to cleanse the outward body and the blood of the lamb or whatever was made a sacrifice would be sprinkled over the people for their sins. Now I see at the cross Jesus as the sacrifice for that day, water and blood came out too. Meaning water goes hand in hand with the blood.