Could Titans have children with mortals and produce demigods?

Selene (the Titan goddess of the Moon) loved Endymion, who lain in a cave on Karian Mount Latmos in eternal youth, with him Selene had fifty daughters - the Menai, the goddess of the lunar months.

Granted, these daughters are called goddesses even born of a mortal parent; so I doubt a child of a Titan would be simply a "demigod".