The Wiggles' Lachlan Gillespie left covered in milk as he feeds his twin girls ...

Lachlan 'Lachy' Gillespie has learned his first 'dad lesson' after welcoming surprise twin daughters with fiancée, Dana Stephensen on Friday. 

The Wiggles performer, known as The Purple Wiggle, shared an Instagram stories image in which his shirt was covered in spat-up breast milk. 

He captioned the comical photo: 'Lesson one: When dad bottle feeding express milk for the first time don't get over excited and feed her too much'. 

Oops! Lachlan 'Lachy' Gillespie (pictured) has learned his first 'dad lesson' after welcoming surprise twin daughters with fiancée, Dana Stephensen on Friday. The Wiggles performer, shared an Instagram stories image in which his shirt was covered in spat-up breast milk

Oops! Lachlan 'Lachy' Gillespie (pictured) has learned his first 'dad lesson' after welcoming surprise twin daughters with fiancée, Dana Stephensen on Friday. The Wiggles performer, shared an Instagram stories image in which his shirt was covered in spat-up breast milk

A second photo shared the same day showed Lachlan at the hospital, holding both his daughters. 

He captioned that image, in which he beamed and while wearing a surgical mask:  'Doubly happy'.   

Lachy and his ballet dancer fiancée welcomed twin daughters on Friday.  

He captioned the comical photo: 'Lesson one: When dad bottle feeding express milk for the first time don't get over excited and feed her too much'. A second photo shared the same day showed Lachlan at the hospital, holding both his daughters

He captioned the comical photo: 'Lesson one: When dad bottle feeding express milk for the first time don't get over excited and feed her too much'. A second photo shared the same day showed Lachlan at the hospital, holding both his daughters

Fans were left in complete shock - with the pair never having revealed the pregnancy -  when The Wiggles performer unveiled the new arrivals on Friday evening. 

In an Instagram post, the 34-year-old shared a photo of his newborn daughters - Lulu and Lottie - resting with their mother Dana, 34, as he looked on lovingly. 

He wrote in the caption: 'Oh Lulu and Lottie, your mummy and daddy love you with all we have - you are both so beautiful - and I would love to sing to you both forever'. 

Shock! Lachy and his ballet dancer fiancée welcomed twin daughters on Friday. Fans were left in complete shock - with the pair never having revealed the pregnancy - when The Wiggles performer unveiled the new arrivals. Lachlan and Dana pictured with their daughters

Shock! Lachy and his ballet dancer fiancée welcomed twin daughters on Friday. Fans were left in complete shock - with the pair never having revealed the pregnancy - when The Wiggles performer unveiled the new arrivals. Lachlan and Dana pictured with their daughters  

Neither Lachlan nor Dana gave any hint that they were expecting, and their social media accounts do not show many recent photos.  

Fans were stunned, with many voicing their complete shock at the news. 

One person commented under the photo:  'Whaaattt! Congratulations to you both' while another added: 'WAIT WHATTTTT'. 

Someone else added: 'Wow didn't see that coming congratulations to the three of you!'  

Lachy wrote in the caption: 'Oh Lulu and Lottie, your mummy and daddy love you with all we have - you are both so beautiful - and I would love to sing to you both forever'

Lachy wrote in the caption: 'Oh Lulu and Lottie, your mummy and daddy love you with all we have - you are both so beautiful - and I would love to sing to you both forever'

Who knew? Fans were stunned, with many voicing their complete shock at the news

Who knew? Fans were stunned, with many voicing their complete shock at the news

The couple announced their engagement in April in a sweet Instagram post, with Lachy writing: 'On Thursday night, Dana asked me to marry her at home under a fairy light sky and a very excited little boy in a beautiful bow tie.' 

In the photo, Lachlan was pictured cuddling up to Dana and Dana's son Jasper, four, inside a bedroom festooned with fairy lights. 

The couple, who went public with their relationship in October, beamed with joy as they cuddled up for the milestone photo. 

Congratulations: Lachy announced his engagement to ballet dancer Dana after she proposed to him at home in April. Pictured with Jasper - Dana's four-year-old son from a previous relationship

Congratulations: Lachy announced his engagement to ballet dancer Dana after she proposed

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