United Kingdom, April 2 -- Blake Lively joked she is regretting teaching her children how to "read a calendar" after she was victim of a toilet prank on April Fool's Day.

The 38-year-old actress and her husband, fellow actor Ryan Reynolds, have four children together, daughters James, 11, Inez, nine, and six-year-old Betty, as well as three-year-old son Olin.

And the It Ends With Us actress was caught out by the youngsters on Wednesday (01.04.26) when she went to use the loo only to discover it had been covered in plastic wrapping, and decorated red.

Blake took to Instagram to share a snap of her kids' playful prank, and she wrote in the caption: "I knew I never should've taught them how to read a calendar."

Ryan previously admitted h...