Mary Lou McDonald not present for speech
Nineteen Sinn Féin TDs sat quietly in the Chamber as Mr Adams recalled his version of helping the Stack family meet a mystery IRA volunteer to get details of their father's cold-blooded killing.
However, Ms McDonald who has shown unfaltering allegiance to her leader throughout a series of controversies was one of the three TDs absent.
A party spokesperson told the Irish Independent she was at home sick.
It recent days Ms McDonald has given a different version of events from Mr Adams in relation to his dealings with the Stack case.
In a newspaper interview at the weekend she said Mr Adams provided the names of four people who may have information about the murder to gardaí, without delay.
But in his Dáil speech Mr Adams stuck to his timeline that he received the names in 2013 from Austin Stack but didn't contact gardaí for two and a half years.
He accused Fine Gael and Fianna Fáil of seeking to "exploit this issue as part of their election campaign of 2016".
In an interview at the weekend, Ms McDonald said: "I think that people have an entitlement to their good name and my colleagues are entitled to that."