Rama volunteered to go to Jungle to emancipate the oppressed tribals.Some say Sita was actualy daughter of Ravan and by curse Ravan could not touch any other woman so he could take Sita to his place. He very well knew that after him , the Rakshash Community which he was able to manage would go out of control and so he planned their downfall himself.He worshipped Ram while taking Sita to his place. Shankar very well knew his son but changed his physique because he could not be just like a human.He brought back ganpati in the form of Ganesh.