The father of two boys allegedly murdered by their mother has urged their friends to "make sure they always live inside all of you" at an emotional farewell.
A funeral service for Russell Smith, 11, and his nine-year-old brother Ben, was held in the NSW Blue Mountains on Wednesday.
The boys were allegedly stabbed to death by their mother on September 10.
Their father Nick Smith delivered a moving eulogy pleading for his sons to be remembered by their friends.
"You are going to go on and have these amazing lives … but one thing I do ask is, every time you come back to the Blue Mountains … please go visit the boys (and) tell them all the great things you've done since you last saw them," he said.
"Make sure they always live inside all of you."
Russell was remembered as a cheeky boy who loved his music and the Penrith Panthers NRL team.
"You just looked at life with a big, cheeky smile, and just embraced it and ate it up," Mr Smith said.
"I knew that we were going to be best friends … have some amazing adventures together."
Ben was remembered as "gentle old soul".
"You're one of those people that just looked like you had been here before, and you had this real little old face on you," Mr Smith said.
"Boys it's been an absolute, absolute privilege to be your father. I hold you so deeply in my heart.
"You are loved by your family, through your friends, through the community through the school, through your soccer club, through the Panthers, throughout society."
Hundreds of family, friends and members of the Blue Mountains community gathered at the St Thomas Aquinas church in Springwood, with many of the boys' friends wearing Penrith Panthers guernseys.
After the service, children, parents and the funeral directors made love hearts with their hands as the caskets were driven away.
Police charged Patricia Joan Smith, 42, with two counts of domestic violence-related murder on September 13 after the boys' bodies were found at their Faulconbridge home.
Emergency services were called to the house following welfare concerns and the boys' father found their bodies on the same day.
NSW Police said Ms Smith was also found at the scene with stab wounds and was taken to hospital in a critical but stable condition.
The mother's Facebook page is filled with photos of her and the children smiling together, showing them on frequent bushwalks and beach visits.
1800 RESPECT (1800 737 732)
Lifeline 13 11 14
