"Shane, Riley and Travis, I'm with you, have fun, stay safe and warm, stop fighting, stop working, be you, go fishing, tell me what I'm here for.

"What do you want me to do?"

Reverend James Wood shared Stacey Lambert's message to her lost family as 800 mourners gathered in Bega on the South Coast, for a final farewell.

Rev Wood had christened Riley, 4, and 15-month-old Travis, as Ms Lambert and proud dad Shane O'Neill looked on.

On Wednesday, he stood before the single casket carrying their bodies.

The trio drowned off Tathra Wharf last week. Their fishing trip turned to tragedy when the boys toppled into the choppy sea, and their father dived in after them. Ms Lambert had been due to marry Mr O'Neill next year.

During the funeral service, Mr O'Neill's sister told of the romance the couple had shared.

"I've never seen a couple so openly affectionate," Lisa Kennedy said.

"It was the talk of the town and every girl said how romantic he was."

Jimmy Barnes' Working Class Man was played in St Patrick's Catholic Church after a series of slides of Mr O'Neill playing with the boys.

Mr O'Neill's mates choked back tears as the casket came into view, passing through a guard of honour of uniformed Bega Roosters football players, Rural Fire Service volunteers and other emergency services personnel.

Bega all but closed during the funeral, allowing many of its 1000 residents to gather for the service.

An appeal in support of Ms Lambert has so far raised more than $143,000, with much of that donated by Bega Valley residents.

Mr O'Neill would have turned 29 on Saturday.