The duchess has been estranged from her father since 2018. Loveless, who has since died, is the mother of Meghan's two half-siblings.
Officers in Cebu required a court warrant before they could examine the items. Police stated they must identify how the material was obtained before they can consider any criminal charges.
Campaigners describe Cebu as a known hotspot for the sexual exploitation of children, and authorities say they take any such allegations very seriously.
Images of child sexual abuse allegedly belonging to Meghan's father had reportedly been found in his former home in the Philippines.
The duchess was estranged from her father since 2018.
Shared on Friday, Meghan confirmed the existence of the letter and wrote:"I am deeply distressed...
He is reportedly now living in a Florida rehabilitation centre learning to walk again after having his leg amputated.