Caught with her pants down: Mum's embarrassing fail after sharing a seemingly innocent photo of her son's toy display

A mum-of-three has unintentionally shared a photo of herself in underwear online after posting a photo of her son's Mario Kart toy collection in a $20 Kmart Lego display.

The mum posted the image to the Kmart Home Décor and Hacks Australia Facebook group, which has more than 326,000 members, but didn't notice her reflection until others pointed it out.

'I obviously didn't look at the photo before posting - I'm an embarrassment to myself, but least I had a top on today,' she wrote online.

The reflection exposed the woman wearing a white striped t-shirt and black underwear while taking a photo of the display.

A mum-of-three has unintentionally exposed herself in her underwear online after sharing a photo of her son's Mario Kart toy collection placed in a $20 Kmart Lego display

While she was embarrassed, she didn't remove the post from the Facebook group and other mums praised her for her laidback home attire.

'I didn't even notice the reflection until you said something! That is the best! Made my day,' one woman said.

'You're a good sport, you look fabulous anyways and your Mario Kart display is on point,' another said.

'Brilliant! Who needs pants in lockdown,' a third said. 

The mum posted the image to the Kmart Home Décor and Hacks Australia Facebook group, which has more than 326,000 members, but didn't notice her reflection until others pointed it out 

Others were simply impressed with her five-year-old's Mario Kart collection.

'Hot wheels Mario collection is just awesome! I'm 27 and I want this,' one woman said.

'My son would love love love this!' another said.

The humorous social media post was 'liked' more than 900 times and 174 people commented.