Hateful commments have been made about the girlfriend of Stephen Dudley, the Auckland schoolboy who died after a fight at rugby training.
They were made on the controversial social networking site ask.fm, which has already been blamed by some for the suicides of children in the UK and Ireland.
The girl's mother told nzherald.co.nz that the comments were disgusting and horrible. "She's only 14. She's not a horrible girl, she is a beautiful girl, but they've got her believing everything they're saying."
She said her daughter had disabled her profile page.
Ask.fm has more than 40 million users worldwide and has grown in popularity with teenagers but, unlike Facebook or Twitter, the Latvian-run site has no privacy settings. Users can post comments anonymously, which critics say has made it a haven for school bullies.
Last year two teenage Irish girls - one 13, the other 15 - committed suicide after being subjected bullying on the website.
Two months ago a 15-year-old British boy, Joshua Unsworth, killed himself after enduring months of abusive messages on ask.fm.
Some of the hateful messages on his ask.fm profile page included: "You really are a freak" and "you deserve sick things to happen to you."
Ask.fm users must be at least 13 years old to sign up but there are no checks to stop underage users from registering.
The site features a disclaimer that warns users it "allows for anonymous content which ask.fm does not monitor. You agree to use the ask.fm service at your own risk and that ask.fm shall have no liability to you for content that you may find objectionable, obscene or in poor taste".
Hundreds of people turned out to farewell Stephen Dudley on Thursday and many more have left messages of support on social media.
Stephen, 15, a pupil at Kelston Intermediate School, was allegedly assaulted by two other teenagers after rugby training.
His father, Brent, said Stephen was "quite simply the best son a father could ever have".
"My son was better looking than me, smarter than me, he had a bigger heart than me and he shared it with everybody," he said.
Where can I get support and help from?
Below is a list of some of the services available which offer support, information and help. All services are available 24 hours a day, seven days a week unless otherwise specified.
Lifeline - 0800 543 354 or (09) 5222 999 within Auckland
Depression Helpline (8 am to 12 midnight) - 0800 111 757
Healthline - 0800 611 116
Kidsline (aimed at children up to 14 years of age; 4 pm to 6 pm weekdays) - 0800 54 37 54 (0800 kidsline)
Samaritans - 0800 726 666 (for callers from the Lower North Island, Christchurch and West Coast) or 0800 211 211 / (04) 473 9739 (for callers from all other regions)
Suicide Crisis Helpline (aimed at those in distress, or those who are concerned about the wellbeing of someone else; 12 noon to 12 midnight) - 0508 828 865 (0508 TAUTOKO)
Suicide Prevention Information New Zealand - www.spinz.org.nz
Youthline - 0800 376 633, free text 234 or email email@example.com
What's Up (for 5-18 year olds; 1 pm to 11 pm) - 0800 942 8787
www.thelowdown.co.nz - visit the website, email firstname.lastname@example.org or free text 5626 (emails and text messages will be responded to between 12 noon and 12 midnight).