King Frederik and Queen Mary of Denmark laughed it off when they were asked about their daughter Princess Isabella recently wearing a headline-making t-shirt.

Isabella, 18, attended the Smukfest festival earlier this month sporting a shirt that read “F—– Him Yesterday” in Danish with an arrow pointing right. According to BILLED-BLADET, the top is a piece of merchandise from the band Suspekt, which was playing at the festival, featuring one of their song lyrics.

Her parents addressed the eyebrow-raising outfit choice on Aug. 26 during a visit to Samsø.

Queen Mary, 53, said in response to the outlet’s question, “My first thought was, ‘Is she completely gone?’ ” according to a translation.

The reply made King Frederik, 57, laugh beside his wife as she added, “Let’s put it this way, some decisions are better than others,” before moving on.

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Princess Isabella also made headlines in April for her 18th birthday festivities, including a regal new portrait (where she sported her first tiara!) and a gala event.

Like his sister, Crown Prince Christian also attended the music festival, described by Music Festival Wizard as “Denmark’s 2nd largest camping festival.” This year’s event featured performances by Will Smith, 50 Cent and Shawn Mendes.

King Frederik and Queen Mary are also parents to 14-year-old twins Prince Vincent and Princess Josephine.

Since the summer music festival, Prince Christian, 19, has returned to his military training. On Aug. 14, the heir to Denmark’s throne was photographed participating in the Danish Armed Forces’ Lieutenant’s Training Course at Antvorskov Guard Hussar Barracks in Slagelse, wearing a camouflage uniform.