According to the book "Before France & Germany" by Patrick J Geary, ISBN 0-19-504458-4, p 232, Chlothar married four times, Radagunda, Irgund, Aregund, and Chunsia. There is no indication which wife is the mother of which child.

From the book "The Birth of France: Warriors, Bishops and Long-Haired Kings" by Katharine Scherman, 1987, ISBN 0-394-56089-2, page 3-4:
At the old monastery of Saint Médard, Soissons, France, is one of France's shrines. At about 560, while Lothair [Chlothar] was still reigning as King, Saint Médard the Bishop ended a lifetime of good works and died famed for his holiness. King Lothair had him buried with great pomp in the city of Soissons, and began to build over his remains the church which his son Sigibert later completed and embellished. A year after the saint's death, it was the turn of King Lothair himself. The Merovingian king of all the Franks died on the first anniversary of the burning to death, on his order, of his rebellious son! Lothair's own death outraged him: "What manner of King can be in charge of Heaven, if He is prepared to finish off great monarchs like me in this fashion?" A blank coffin at the monastery is his only memorial.