The bodies of a missing 36-year-old Turkish woman and one of her three children, aged 1, were found on the Turkish side of the Evros River, Turkish news media reported on Friday evening.
Turkish and Greek police boats continued their search for the woman's older sons, aged four and six.
The family went missing after their boat capsized in the Evros River early Thursday. They are believed to have fled Turkey for Greece along with the woman's husband and four others, all Turkish, who managed to swim to the Greek side of the border where Greek authorities picked them up on Thursday.
Four Turks were handed suspended three-month sentences after being found guilty of trespassing in a restricted area. Two of them reportedly stated that they were journalists.
Hundreds of Turks have sought asylum in Greece since a crackdown by Turkish President Recep Tayyip Erdogan in the wake of a thwarted coup against him in 2016.