A parent has gone on an enraged rant after one of their children was invited to a classmate’s birthday party – but their twin sister wasn’t.

“I know the birthday kid decides whom they invite. I know you’re not entitled to an invitation. But wtf is going on with inviting only one twin back when both of them have invited your kid to their own birthday party?!” asked the parent on Reddit.

They explained that their four-year-old twins had recently had a joint birthday party at an indoor playground.

Then, at daycare drop-off, their son found a birthday invitation on his shelf from one of the kids who had been at their party. But their daughter didn’t. “The puzzled look on her face broke my heart,” they added.

The parent said they know their daughter isn’t entitled to an invitation, but they were still clearly very annoyed about it – “if you really can’t convince your kid to invite her ... do me a favour and don’t invite her twin either,” they wrote, adding that the whole situation “sucks”.

Is it ever OK to invite one twin – and not the other –........

© HuffPost