Russell Smith, 11, and his nine-year-old brother, Ben, were allegedly murdered by their mother on September 10.
As their mother waits behind bars for her next court appearance hundreds of family, friends and members of the Blue Mountains community gathered to farewell the much-loved boys on Wednesday.
Mourners brought flowers to commemorate the lives of the boys. (Bianca De Marchi/AAP PHOTOS)
The funeral was closed to media, but the boys' friends were seen entering St Thomas Aquinas parish sporting Penrith Panthers guernseys and flowers.
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 Smith was also found at the scene with stab wounds and was taken to hospital in a critical but stable condition.
Many friends of the boys wore Penrith Panthers guernseys. (Bianca De Marchi/AAP PHOTOS)
The mother's Facebook page is filled with photos of her and the children smiling together, showing them on frequent bushwalks and beach visits.
The boys' father Nick Smith, who does not live at the Blue Mountains home, expressed disbelief at the tragedy.
"The loss of our two beautiful boys has caused unimaginable pain and distress," he said in a statement last week.
"Russell and Ben were happy, funny, outgoing boys and were very much loved by their family and friends."
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