Canine actor with posthumous credits

I recently corrected the birth and death date information for this noted dog actor, Spike (1952-1962). Previously, it had the death date at 1995, which would have made the dog at least 40 years old at time of death. Obviously, this was not correct, but Find a Grave had the correct information available, so that part got fixed.

However, now that the death date has been corrected, it has become apparent that four of the titles Spike is credited on according to IMDb were released several years after his death. Presumably, these credits should be transferred to a different canine actor. It's possible that there were two Spikes who shared a name by coincidence, or it could be that another dog was chosen as Spike's successor. I really don't know. The bio does mention that Spike had a son named Junior, who has a few credits of his own, but there's no indication of whether or not this dog took over Spike's roles in the late 1960s, although it is certainly a possibility.

If anyone has any information that could clear this up, it would be greatly appreciated.