Basilk

I feel as I may have dreamt this. It is the "prequal" to Suddenly, last summer. It takes place in the Galapagos Islands. Katharine Hepburn is the mother, I think Robert Wagner is the son. I remember a great cast. The movie is filmed on a yacht and the group has gone to the Galapagos to watch the hatching of the sea turtles. Any help is welcomed.