New Melbourne mum in critical condition after her husband drove their car into a dam.

Two weeks ago, after a traumatic pregnancy, Kerry Budding (Arrow) gave birth to her first child, Jock, prematurely. It had been an extremely difficult pregnancy through which Dr Budding, a clinical psychologist, had suffered hyperemesis gravidarum, the debilitating condition characterised by severe nausea, constant and extreme vomiting, weight loss, and electrolyte disturbance.

This, topped off by the premature birth of her baby, led to a difficult year for the much loved clinical psychologist and horse enthusiast.

But on Saturday morning the worst was yet to come as the couple left their Healesville home in Melbourne’s outer east to visit their son Jock, who was still in Mercy Hospital after his premature birth.

Police say that their car somehow plunged into a dam on their property leaving Kerry Budding, 36, in a critical condition.

The Herald Sun reports that at around 10am on Saturday their white Nissan Patrol driven by Phil Budding, 32, veered off-course from their property's driveway and plunged into the dam.

Mr Budding dragged his wife from the submerged car but she had already suffered life threatening injuries.

Paramedics rushed Dr Budding to hospital, she was then airlifted to Royal Melbourne Hospital where she remains in ICU.

Police took Mr Budding into custody where he was questioned, but later released without charge.

An officer told media the circumstances of how the car ended up in the dam “are certainly still under investigation”.

Dr Budding, who had been married to Phil Budding for just over a year had only just recovered from a difficult pregnancy where she suffered the devastating condition, hyperemesis gravidarum.

An illness she said, “has, and continues to, threaten everything important in my life”.

She wrote on Facebook that hyperemesis gravidarum had changed their lives.

She wrote on Facebook: “It isn’t pretty and we sure as hell are not the happy go lucky couple we used to be. We may never be again. But day by day we work through it as best we can. There are tears every day. There is anger every day. There is the potential to fall into darkness so great we may never recover from it. But there is also a life inside of me that was created with so much love.”

During her pregnancy she said: "We have both discussed and considered termination multiple times. There is currently an application for a late term abortion being heard by an ethics committee because it may come to that. But it doesn't have to. So we do what we can with whoever is prepared to help us. And those who are creating conflict or tension or chaos are ruthlessly cut from our team. Because Mickalien will only turn Humanoid if we as a couple get real about the situation we are in, and front up to it head on. Using any means necessary to get all three of us to the other side.”

Her words, written during her pregnancy only show a small part of what she had been dealing with. But with tenacity and bravery she came through her illness, and her and her husband welcomed Jock into the world just two weeks ago.

Tragically, Saturday's accident has cast their world into darkness once again.

On Facebook friends paid tribute to her, urging her to come through the crash.

“As if life hasn't tested her enough. Sending all the strength and healing vibes I can,” wrote one.

Another: “This is just too sad, too tragic and too horrific. She has been through so much.”

And this: “I'm totally in shock after all they've been through already. I pray for her speedy recovery.”

The Leader reports that the major collision investigations unit will continue to probe the scene as they try to discover what caused the car to suddenly veer off the road.

To donate to Kerry's son Jock, click here.