Desmond 'Dessie' Byrne (52) and his sister Muriel Eriksson (62) died in the incident on Thursday afternoon.
The two siblings died after getting into difficulty while swimming.
The holidaymakers had only arrived in Ballybunion days before the tragedy.
Mr Byrne’s teenage son was on the beach as the tragedy unfolded, and he was treated for shock afterwards, before being reunited with relatives.
Mr Byrne, who is originally from Athlone, has been based in Lecarrow in Roscommon for many years and worked as a carpenter and carpet-layer.
His older sister had been living in Malmo in Sweden over recent years but maintained very close links to Ireland.
Ms Eriksson will repose alongside her brother Dessie, at his home in Roscommon on Monday evening from 4pm until 8pm before removal on Tuesday morning to St John's Church, Lecarrow, arriving for Mass of the Resurrection at 12 noon.
Mr Byrne will be buried afterwards in the local cemetery while Ms Eriksson will be cremated on Wednesday at 4pm in Lakelands Crematorium, Cavan.
A funeral notice on RIP.ie said Ms Eriksson died “tragically, alongside her brother Dessie”.
The notice read: “Sadly missed by her heartbroken husband Kris, son John, daughter-in-law My, grandson Liam, brothers Kenny, Donal, Justin and Colm, sisters-in-law Maggie and Nong, Dessie's partner Paulette, aunts Kathleen and Kay, uncle John, nephews, nieces, relatives, neighbours and his many good friends.”
Mr Byrne’s funeral notice said he died “tragically, alongside his sister Muriel”.
“Sadly missed by his heartbroken partner Paulette, sons Dean and Josh, Paulette's daughter Regina and her sons Blake and Jace, brothers Kenny, Donal, Justin and Colm, brother-in-law Kris (Sweden), sisters-in-law Maggie and Nong, aunts Kathleen and Kay, uncle John, nephews, nieces, relatives, neighbours and his many good friends.”
“The Eriksson and Byrne Families thank you for your support at this time.”
Gardaí will prepare a file for a Kerry coroner's inquest next year.