The 22-year-old model posted an image of herself nearly naked and straddling a motorcycle.
"No. Just…no," he wrote in her comments section.
One fan commented, "LOL Alec freaking out."
Some other fans were less worried about Alec's reaction and more concerned about Ireland's safety.
One wrote, "There is no way that is a safe way to ride" and "refer to the owner's manual please."
The publicity from her famous dad's comment has not hurt though. So far, the post has gained over 18,600 'likes' from her 414,00 followers.
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