The perils of putting theory into practice as an election looms
"Sinn Féin is the party of welfare and welfare dependency," Ms Burton has frequently told the Sinn Féin deputy leader.
The Labour Party argues that the 30,000 single mothers are likely to be marooned in dependency and poverty on the lone-parent allowance. The party argues that the latest changes to the lone-parent regime are an effort to alter this by a mix of incentives and supports - and yes, ultimately, some penalties, propelling lone parents towards work.
This one is not new. In 2004-2007, the late Séamus Brennan, as minister for Social and Family Affairs, was pulled back from these kinds of changes by his and Fianna Fáil's realpolitik pragmatism.
But Labour is forging ahead and making it a happy time for Sinn Féin. Ms McDonald was on the attack yesterday, helped by the Tánaiste's hostage to fortune back in 2012, when she said changes would not happen without "a Scandanavian model of childcare".
"Such a system of childcare simply is not available," Ms McDonald said. She put the average cost of childcare at €167 per week and higher in Dublin.
An election looms and yesterday, Ms Burton met a group of her party TDs and promised to look at some detailed changes to soften the income reductions to lone parents.
For now the changes, including a major one on July 1, will continue.
There is a view within Labour that they can battle through.