When Sarah and Liam fell pregnant for the first time, the first few months of the pregnancy were a breeze.

“Everything was pretty normal for the first four and a half months,” Sarah told Mamamia.

“It was pretty healthy – there was no issues with my health or anything.”

But 18 weeks into the pregnancy, doctors noticed something wasn’t quite right.

“At our 18 week scan, they were unable to locate Parker’s foot so we had to go through further ultrasounds and testing. They soon found that he had hand contractures as well,” Sarah said.

“We went through genetic counselling at Westmead Hospital and at 20 weeks, they explained to us that he had Arthrogryposis.”

Watch a promo for the brand new season of One Born Every Minute Australia below. Post continues after video.

Arthrogryposis is a debilitating congenital joint problem. In Parker’s case, he was born with an absent foot – meaning he now uses a prosthetic – and mobility issues from his fingertips to his shoulders.

Despite the complications with her pregnancy, however, Parker’s birth went fairly smoothly.

“Parker was induced a couple of days early because the water was really low,” Sarah explained.

“They decided to induce because less water means less movement. They wanted to get him out and get him moving,” she added.

“I had an epidural almost straight away with him and it was a pretty calm labour. We were both just very calm and hoping for the best.”

The Australian birth stories you haven’t heard before. Three Australian mothers share their birth stories on Mamamia’s daily news podcast, The Quicky. Post continues below.

Today, Parker is almost seven years old.

“He still has his limitations,” Sarah told Mamamia.

“We still do a lot of therapy with Parker. We see occupational therapists and physios regularly. Handwriting and anything that takes fine motor skills is a bit of a challenge for Parker.”

For Sarah, Parker’s condition often comes with a lot of misconceptions.

“We do get a lot of people asking us, ‘What happened to him?’ and ‘Did he have an accident?’,” she said.

“[Parker’s] prosthetic looks like a cast so I find myself explaining regularly that nothing has happened to him. He hasn’t had an accident – nothing traumatic has happened to him. That’s just the way he was born. We just try to educate and raise awareness where we can about people who were born different.”

Since welcoming Parker into the world, Sarah has also taken a new direction in her career – moving from the job search field to disability employment after being inspired by her son’s condition.

And 12 weeks ago, Sarah and Liam’s world changed all over again.

Sarah, 33, and Liam, 36, are one of the couples featured on the new Channel Ten show One Born Every Minute Australia, based at Sydney’s Westmead Hospital – which brings 5,500 babies into the world every year.

On Tuesday night's episode, we'll catch a glimpse of what the birth of Sarah and Liam's second child, Finnley, was like.

But although it seems... uncomfortable to welcome cameras into the birthing suite, Sarah said it was "no different" compared to her birth with Parker.

"To be honest, I didn't really feel a difference," Sarah said.

"It wasn't invasive at all. We met two people when we got there and they put little microphones on us and that was it," she continued.

"It's an opportunity to raise awareness [about Parker's condition] for us. We can't wait to watch it – it's so nice to have all that on film for Finnley as well as for Parker."

Due to the complications with Sarah's first pregnancy, their second pregnancy was treated as a complex pregnancy at Westmead Hospital.

"I had inconsistent contractions for four days beforehand," Sarah said of her birth with Finnley.

"They were painful and they were taking my breath away. It was just too inconsistent and you can't really go to the hospital until they're five minutes apart and consistent," she said.

"We went to the hospital when [the contractions] were five minutes apart and between getting there and having the baby, I think it was only about three hours."

Now, three months later, Sarah is juggling life with a newborn and a child with a disability.

"It's a whirlwind at the moment," Sarah admitted.

"Parker just had surgery last week so I've been at the hospital juggling the two boys. They both have needs – while Parker was having his dressing re-done the other day, I was holding Parker's hand because he was nervous while having to nurse his little brother," she continued.

"I'm just trying to make sure that they're both getting what they need from me. It's learning and it's a juggle but we're getting there."

One Born Every Minute Australia airs on Tuesday nights on Channel 10 at 8.30pm.

For more on this topic:

• Pain thresholds, fighting and 4am breaks: Natascha from One Born Every Minute on what it's really like to be a midwife.
• "She's in there." What no one tells you about raising a child with a disability.

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