There's a small problem with Ivanka Trump's tweet to her son

Donald Trump has the unfortunate habit of making himself look rather foolish on Twitter.

It appears the condition is hereditary.

Ivanka Trump, the President-elect’s daughter and Executive Vice President of her father’s company The Trump Organisation, has a son called Theodore.

Ivanka tweeted the following about him:

Cannot believe that Theodore is eight months old today! Happy birthday little teddy bear!

Now, putting the proximity of the flames from the eight-month-old baby aside, you might notice the other problem with the tweet. Others certainly did:

That's right: birthdays happen on a year-by-year basis. Theodore is only eight months old.

People on Twitter were brutal...

...swift...

...seriously.

Maybe she meant something else?

Oh. Dear.

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