Jonathan Pugsley said her 15-year-old daughter Ciara was an outgoing, bubbly girl.
"She wasn't kind of a retiring type, she'd always like to be there at the forefront of the conversations and she was very good. That's really how we can remember Ciara," he told UTV Live Tonight.
Ciara was adored by her father and her mother, originally from Omagh, and brother Daniel.
Living in Dromahair in Co Leitrim, the teenager was vibrant and intelligent. She loved her horses, karate, football and anything that involved sport.
Jonathan described the last few weekends the pair spent together, enjoying the countryside and adventuring in a forest.
"Beautiful, beautiful smiles out of her and great chat and just some of the unique sayings she had, it was fantastic and she was just starting to learn how to water-ski," he said.
On 19 September, Ciara went to school as normal. But that evening, without any warning, she took her own life.
How morally can people even operate these sites where these comments are being made and they're open for everyone to see. They're open for the site operators to see them and yet they seem to do nothing about it.
"The evening before, the Tuesday she had played a football match and she was looking forward to a minor football match on the Saturday - it was a final and she had been picked out for that," Jonathan explained.
"She seemed happy and just normal Ciara, so there was no indications that anything was wrong at all."
After desperately searching for answers, the family discovered that she was being bullied online via the website Ask.fm, which allows people to leave questions for account holders, and can be used in conjunction with Facebook.
"She was being taunted about a number of things. They were saying she was ugly, she was fat. All sorts of bits and pieces you know," her father explained.
"A lot of it is obviously blatantly untrue but I think when you are a young teenager you take some of these things to heart."
Jonathan said he was disgusted at how people hid behind their anonymity to abuse her. He also expressed his anger that the website is still allowed to operate.
Incidents of cyberbullying is three times higher than in 2007, with just over 15% of year six pupils in Northern Ireland saying they have been a victim, according to the Department of Education.
These faceless, nameless people are coming into our homes and abusing our children and that has to be morally, totally unacceptable.
Ciara's father has warned every parent to be on their guard.
He is convinced that parents don't understand the dangers their children are being regularly exposed to on the internet.
"If you're at home and the door bell rings or someone knocks at the door and your son or daughter goes to open the door. They open the door and there is a person there. The person doesn't have a name. Doesn't have a face and yet they let them in to your house, in to your home, they let them in," he described.
During a eulogy at Ciara's funeral, mourners were told how she did not want to die, but was driven to it by bullies.
Jonathan has said while parents have a key role to play, he has called for stronger involvement from schools and the Government to regulate the internet sites which teenagers use.
Gardaí are carrying out an investigation into the case. UTV Live Tonight requested a comment from Ask.fm, which is based in Latvia, on three occasions, but no response has been received.