Two people have been arrested on suspicion of child neglect following the death of a baby boy.
Police and paramedics were sent to a house in Clynderwen, Pembrokeshire at about 13:45 BST on Friday.
A four-month-old boy was pronounced dead at the scene.
A 19-year-old woman and 23-year-old man have been arrested and inquiries are ongoing, Dyfed-Powys Police said.