The three following paragraphs were as I originally posted them. I then stated that I was searching for the “three sisters from Herentals” and described what research steps I had taken. Thanks to the edition Kempen of the Gazet van Antwerpen and their reporter Hans Otten, the sisters have been identified as the four sisters: Madeleine, Gusta, Maria, and Julia of the Claes family of Vorselaar. The two living sisters, Madeleine and Gusta were interviewed for the newspaper story that appears below.
My information as originally posted:
Karst Smit and the other marechaussees in Hilvarenbeek and Baarle-Nassau were responsible for patrolling the Dutch-Belgian border to, among other things, prevent smuggling. During the course of this work, Karst Smit and his fellow marechaussees came into contact with three blonde sisters, ages 17-20, from Herentals [actually Vorselaar] who were smuggling food from The Netherlands into Belgium for their family. On one occasion Smit discovered that his commander at the marechaussee headquarters in Baarle-Nassau had arrested the three girls and locked them up in the cells. On his own authority, Smit released the girls, later asking his angry superior, “How would you like it if your daughters were treated like criminals?” The girls headed home on their bicycles.
The girls’ parents invited Smit and one of his top aides, David Jonkers, to spend the weekend at their home in Vorselaar. Smit later wrote that the parents proved to be very respectable people, owners of a small factory that was out of work because of a lack of raw materials. The parents agreed that escaping French prisoners of war could stay at their home over night on their way back to France. When Karst and his men became very busy with helping Allied airmen, the three sisters took over the responsibility of moving the Frenchmen across the border to Herentals [Vorselaar] as well. Karst later wrote that, “This always went perfectly because they knew the smuggling lanes even better than we did.” He said that even years later he could remember the place where he would meet the girls, “a huge oak tree in the middle of a field, so that we could see ‘danger’ coming. It was between Esbeek and Lage Mierde.”
Eugene van der Heijden wrote that in the autumn of 1945 Karst took him to meet some Belgian friends on the border near Poppel, who proved to be three very attractive young ladies, but Eugene didn’t recognize them. To his amazement, Karst explained that they were the smugglers from back in 1943. Eugene wrote, “They belonged to a respectable family from Herentals.” He thought there was some family connection to the future Belgian minister Willy Claes.
News story as it appeared in the Gazet van Antwerpen, Aug. 31, 2010:
WWII Netherlands Escape Lines 
I”m the son of Julia Claes. My mother (who died in 1979) often told me about her smuggling adventures, which she found very exciting, but I’m quite sure that she didn’t realize she was working for the resistance smuggling people over the” Dutch – Belgian border. What she did tell me was that she wouldn’t have dared to smuggle anything over the border if she shad known of the existence of concentration camps and the way the nazi’s dealt with people who stepped out of line. So she may not have been a hero after all, but she certainly was a wonderful (and beautiful) woman and mother.