but that is up to Joris to tell

I think Joris was 15 years old when he fell in love with Eva. They eagerly wanted to spend a night together and make it an attentive, festive event and had thought that it would be nice to go to sea to make this happen.  Joris asked Caterina if he could spend the night with Eva on the beach. Caterina didn't think that was such a good idea. You never know what kind of scum is out there all night along the coast.

Joris and Eva came up with another plan. They saved money for an overnight stay in the Kurhaus, a beautiful and stately hotel on the coast in Zandvoort.  They booked a room, which was very pricey. Joris told his parents that he was going to sleep with a friend and Eva told her parents that she would stay with a friend. Because they could suspect that their parents wouldn’t approve. Not even with a roof over their heads.

Joris told their plan in confidence to Nelleke, Caterina's sister. Nelleke happened to be with Caterina and Rien that evening.

The evening that Joris and Eva secretly stayed in the Kurhaus, Eva's mother called the mother of the friend mentioned by Eva.  Without suspecting anything, she said that Eve was not with them. Then Eva's mother called Caterina to ask if Eva was with Joris; which turned out not to be the case. The mothers could have guessed that Joris and Eva were together, but where? Nelleke then unfolded their secret. Eva's mother was angry and called the hotel. The rest of the story was self-explanatory. The festivity was over, and the next morning the young couple drifted home with their tails between their legs.

So regrettable!  Just let these youngsters enjoy their wild plans. I would have sent them a champagne breakfast.

I believe that the second attempt was not wrong either, but that is up to Joris to tell.