It is common for people to be proud of their baby photos and post them on Facebook. But one user was so fed up with seeing an Australian woman's constant updates about her six-month-old daughter, the person sent her an anonymous letter in the post telling her "we don't care".

It read: "I have got together with a few of the girls and we are all SO OVER your running commentary of your life and every single thing Addy does.

"Look, we all have kids that we are besotted with – guess what – every parent thinks their kid is the best ever.

"But we don't ram it down everyone else's neck!!! She wears a new outfit – well take a photo and send it PRIVATELY to the person who gave it to her – not to everyone!!!

"She crawls off the mat – we DON'T CARE!!!!! She's 6 months old – BIG DEAL!!!!

"Stop and think – if every mother posted all that crap about their kid – I'm sure you would get over it pretty quickly."

Jade Ruthven, 33, was left angry by the letter but has had the last laugh by posting it to Australian comedian Em Rusciano who then posted to her thousands of followers on social media.

Ruthven told Daily Mail Australia: "At first I was in shock and thought this letter must be a joke. I read it and re-read it about four times. I was shaking with anger and shock to think a so-called friend of mine could be so heartless and gutless to not even sign their name."

But she added she had no clue as to who would send the letter to her. Ruthven said: "I don't think I have had an enemy in my whole life."

Comedian Rusciano also wrote an opinion piece to about the saga. Defending Ruthven's actions, she said: "It's not like she busted into their houses armed with life-size portraits of her child dressed as a tiny adorable pumpkin and demand that they be hung on every wall.

"Obviously in some people's opinion she's been overdoing it on the proud mother moments. Annoying, yes. Worthy of an anonymous poison pen situation, no."