A boat carrying 14 people left Gizo for the Shortland Islands but failed to reach its destination.
The body of a woman was found near Zinoa Island on Tuesday - about 100 kilometres from the Shortlands.
Health officials on Taro Island had confirmed the body was that of a child, which is being kept at Taro Police Station for further investigation.
Police said a family, travelling from Supsizae to Taro in Choiseul Province to attend a church service, found the child.
The bodies of a woman and a child were recovered, police said.
