But she allowed her husband Eddie to take over the handling of the funds.
At Christchurch District Court, the summary of facts shows that on August 1, 2016, Eddie Quirke logged into his father-in-law's Milligan's Radio Ltd bank account without authorisation and transferred $3000 into his own personal bank account.
That was the same day his father-in-law had died.
Three days later, another $3000 was transferred by Quirke into his bank account.
Between August 12 and September 13, 2016, Edward Quirke accessed his dead father-in-law's business bank account on 10 more occasions and withdrew a total of $34,000.
The total amount taken out of the Milligan's Radio account by Edward Quirke was $40,000.
A further $12,600 was withdrawn from Robin Milligan's personal account by his son-in-law.
"Between 20 September 2016 and 14 December 2017, Mr Quirke accessed another (BNZ) bank account in the name of Robin B Milligan on 76 occasions, withdrawing a total amount of $1,340,900," the summary of facts says.
Shirley Milligan would only find out about the offending two years later in January, 2018.
She reported the matter to police.
Police investigations found that more than $560,000 was spent on gambling by Eddie Quirke, about the same amount on money transfers, more than $128,000 on assets and just over $121,000 in ATM withdrawals.
Claire Quirke's personal bank account also received money transferred from her father's accounts.
The couple declined to make a statement to police.
This afternoon at Christchurch District Court, Eddie Quirke's defence counsel Anselm Williams said a significant amount of the stolen money had gone on online gambling.
He pleaded guilty to four charges of theft and four charges of accessing a computer system for dishonest purposes.
Judge Gilbert said Eddie Quirke's pre-sentence report was "not particularly positive" and didn't include much remorse or awareness of the impact his offending has had.
He jailed Eddie Quirke for four-and-a-half years and ordered him to pay $30,000 in reparations – by way of selling six vehicles he owns, including an Audi, Ford Ranger ute, and Jaguar XJ which needs repairs.
Claire Quirke's defence counsel Nick Rout described it as a "tragic" set of circumstances where she has ended up in court facing one charge of theft by a person in a special relationship.
And while Rout said she doesn't blame her husband entirely, it's clear that he was more to blame.
She is willing to undergo counselling, Rout said, and the relationship with her mother is "capable of full repair".
Judge Gilbert sentenced Claire Quirke to eight months of home detention and also ordered her to pay an extra $30,000 reparation.
