More than 100 separated fathers took to the streets of Dublin today to demand more rights to see their children.
They marched from the Four Courts to the GPO to highlight their campaign for changes to the family court law.
The event was organised by The Unmarried and Separated Fathers of Ireland.
Noting that many men will not get to see their children this Fathers' Day, the support group called on the Government to hold a referendum on constitutional change to enshrine the rights of unmarried parents.
Spokesman Ray Kelly said fathers were discriminated against simply because they were men.
"Throughout Ireland many fathers who are separated will not have spent time with their kids," he said.
"This means that these fathers will not have access to their children this Fathers' Day.
"People must take into consideration the long-term effects it can have on a child by denying the father access or limited access to him/her.
"There have been a rising number of young men and women attempting and/or committing suicide. Suicide has now become the single most common form of death among those experiencing family breakdown."