She was appointed as a Senator for South Australia on 21 September 2021, to fill a casual vacancy caused by the death of Alex Gallacher.

[1] Grogan was born to Irish parents in London, England.

Her father Larry Grogan was a shop steward with the Transport and General Workers' Union.

[2] Grogan was previously CEO of the South Australian Council of Social Service (SACOSS) until 2009, when she worked as chief of staff to the federal MP for Hindmarsh, Mark Butler.

In 2019, she joined the United Voice trade union as a senior political officer.