Frederick, or Tres, the oldest son of Gwapings members and Anne Carlene, their daughter-in-law, recently had their first child.
Eric shared photos on social media of himself holding his grandchild while introducing him to the world.
Eric wrote the caption, "My Apo 'Leo'," Eric.
The matinee idol was excited to become a grandfather last August.
Eric also offered advice to his son as he enters the world of fatherhood.
Be true to your wife. Love her. Enjoy-in mo lang. Huwag kang magpapapaniwala sa ibang babae ha," Eric told Tres.
Eric's son appears to have married his partner in September, according to Instagram photos.