That's a gel battery in your car, right Bob? Not an AGM.
Do use distilled water in you floodie if it needs it. But you probably knew that.
The other possibility is overcharging, resulting in loss of H2O and dry plates which then "sulfate" immediately. It will be interesting to see what condition yours is in.
Of course, now, my half baked theory includes almost all the possible causes of early battery death. That's what you get for 0 data. I'm a seasoned practitioner of Hunchology.
In case you go for the Yellow top, there is a kit available. I'll see if I can dig up the link.
Here's the deluxe:
Replaced 12v battery with Optima - PriusChat Forums
And the budget version:
Battery Replacement - Economy Method - PriusChat Forums