She married Childers, who was then a senior Fianna Fáil politician and government minister, in 1952.
The couple's mixed marriage (Erskine Hamilton Childers was an Anglican, she a Roman Catholic) caused some controversy; the then Roman Catholic Archbishop of Dublin, John Charles McQuaid tried to discourage them from marrying. They eventually opted to marry in Paris. (McQuaid reportedly later apologised to the couple for his behaviour.)
Erskine was elected President of Ireland in June 1973. An acclaimed president, the popular Childers died suddenly in November 1974. The political parties secretly agreed a deal to make Mrs Childers the new president. However, a political dispute in which a partially deaf Fine Gael minister in the National Coalition government, Tom O'Donnell, misheard a journalist's question about Mrs Childers and confirmed that she would be the next president led the plan to collapse. Her late husband's political party, Fianna Fáil, withdrew its support for her and instead proposed former Chief Justice Cearbhall Ó Dálaigh.