
I got this info from a website:Shiva and Parvati are often shown as sitting in happy, intimate embrace. They also like to discuss philosophy. Shiva taught Parvati on Vedanta (transcendent knowledge), while Parvati tought him Sankhya (cosmological knowledge). Both were perfected yogis.
After their marriage, they left for mount Kailash and immersed themselves completely in a sexual intercourse so strong that the deity of desire Kama was reborn when their sweat mingles with his ashes. Their love was so intense that it shook the cosmos and frightened even the gods.
The balance between male and female can also be obtained in marriage, when both partners complement each other to form an ultimate oneness, which is the source of creation. When Shiva does his destructive Tandava dance, Parvati is said to complement him with a slow, creative step of her own, calming him with her soft glances. While Shiva shows a wilder nature that is both ascetic and erotic, Parvati stands for the middle path of the householder. As Shiva exulted in his romantic dalliance with her, the true mother in her longed for a child. Shiva resisted the life of a householder, but Parvati's desire for it was greater than his resistance. Hence first Ganesha was born, later also Kartikay.