I believe there is something genetically incompatible between Henry and Mabel, as this was their third litter, and there has only been one kitten to survive. Mabel will be spayed to prevent this tragedy from happening again. I will begin looking for a more suitable female to pair with Henry.
Rest peacefully little Mippey. We loved you with all our hearts for the 25 days you graced us with your presence. We will meet again one day at the Rainbow Bridge.