Ivanka Trump wished her son a 'happy birthday', and Twitter roasted her for it.

Ivanka Trump has defended her decision to wish her son Theodore a “happy birthday”, after copping flak on Twitter.

You see, little Theodore James Kushner hasn’t even reached his first birthday. Not even close — he’s only eight months old.

So as you can imagine, Twitter users were quick to mock the 35-year-old for her slightly overzealous celebration of the milestone. Many pointed out, quite rightly, that if Teddy is eight months old, it’s not actually his birthday.

Twitter user and animal rights activist Steph Corneliussen was one such person, mocking the entrepreneur in a tweet that has since been deleted.

Trump, a mum of three, responded to Corneliussen’s criticism by cheerfully agreeing that it wasn’t her son’s actual birthday… but she was simply following a ‘new parent’ rite of passage.

The former fashion model’s tweet seemed fairly innocuous considering social media feeds are often filled with proud parents sharing a cute snap of their child on the day the become a month older, often accompanied by a similar statement of disbelief.

And while most parents don’t wish their child a “happy birthday” in these posts, people’s responses to Trump doing so have been harsh.

Equally fierce have been the people defending the soon-to-be first daughter, with Steph Corneliussen allegedly receiving “death threats”.