If you assume GHWB has an equal probability of passing away on any given week of the year, and the state funeral would be held during the next business week you have a

(1/52) * (1/5) = .0038 probability of the state funeral being held on December 5th.

So in a naive, perfect probability world you would expect this to occur less than 4 in 1000 times. It would be even less likely in the real world.