I'm having the same problem but I'm not sure I want to move the boulder because of the eyes behind it. It could be a monster that kills all my villagers and I've only just got them to start having babies.
The Golden Child: To get the golden Child: If you have both the temple and the idol done, and level 3 fertility, then you should get the golden child if you drop a mom and baby in the lagoon.
To get the Fruitless Tree to Fruit: Drop the Golden Child on the fruitless plant. Butterflies will appear that will follow the Golden Child for a while. He will run off but the butterflies will stay and pollinate the plant. It will take a couple of tries.
Boulder: The Golden Child will move the boulder and you then can place a villager into the cave. It has no monster, which kills your babies, so no worries.
Good Luck!
Lagoona
3 of Clubs
Posted on Wed Jan 26 18:32:52 PST 2011