World's First: Youngest Alzheimer's Patient Ever Gives Birth
At 31, Doig is one of the youngest sufferers in the world and the first to give birth.
Her daughter Emily was delivered by C-section at Hornsby Hospital but Rebecca hasn't been able to hold her child.
"Emily is perfect," the Daily Telegraph quoted Rebecca's hubby Scott, as saying.
He went on: "She's a very beautiful little thing and very healthy.
"The road ahead is going to be extremely difficult - there's no two ways about it. We take every day as it comes because there is not a lot that we can do about it.
"If you sit there and start thinking about things, you will just get depressed. I can't do that because I've got a wife and now a little girl to look after."
Scott is, however, a little relieved because Emily does not carry her mum's defective PSEN1 gene that would have predisposed her to Alzheimer's.
Rebecca was an outgoing and bright young woman before the disease struck her. The first signs of the deadly disease started showing when she kept losing her handbag and misplacing other items.
By 2008 her condition worsened and she lost a number of jobs due to repeated mistakes.
Ultimately, she was diagnosed with an extremely rare form of Alzheimer's last August.
The disease has caused a part of her brain that controls emotions to shrink.
Scott said: "It's hard to see your wife lose that.
"Once she was so energetic and youthful. But she's my life and I'm not giving up on her."
The Doigs are now struggling financially with a mortgage, growing needs for care and only one wage.
To add to their woes, Rebecca has been refused a disability pension.