In America, a woman has died after a gender reveal surprise went horribly wrong.
It happened when a home-made device that was supposed to discharge a blue or pink powder instead exploded like a pipe bomb.
Gender reveal parties are held by expectant parents who want to let family and friends know if they're having a boy or a girl.
They have recently become extremely popular, and include stunts like cutting into a cake which reveals either a blue or pink centre.
Other reveals are more elaborate.
In this one in Iowa, the expectant parents made a home-made device which was supposed to emit a blue or pink powder.
However, the way in which it was taped together meant that when it was set off, it exploded "like a pipe-bomb".
A piece of metal from the contraption flew across the family's garden, striking a 56-year-old relative in the head.
“This family got together for what they thought was going to be a happy event with no intent for anyone to get hurt,” Sheriff Jason Sandholdt said in a statement.
What ended up happening was that Pamela Kreimeyer, a wife, mother and grandmother, was killed by a piece of metal where a metal stand gunpowder and coloured powder were involved."
Police have expressed condolences with the expectant parents, and warned about the dangers of using explosive materials.
