March 14 was just another day in Katrina Goss's busy life.

Nothing seemed amiss when her three sons came home from school, but just a few hours later she found 11-year-old Tysen's lifeless body in a cupboard.

The boy, from Michigan in the United States, died when his life support was switched off three weeks after his suicide attempt as the result of an online prank.

Now she's told the story of his death from her point of view.

"All I've ever done is try my hardest to protect you, but I couldn't protect you from this. I'm so sorry my beautiful sweet baby," she wrote in an emotional Facebook post. Photo / Facebook

"All I've ever done is try my hardest to protect you, but I couldn't protect you from this. I'm so sorry my beautiful sweet baby," she wrote on Facebook.

The 41-year-old told the Washington Post that on the day he committed suicide, the young ice hockey player seemed "happy" and was "proud" that he had remembered to go to his tutoring session without being reminded.

She baked him some treats as a reward, and as usual he went to his room after dinner - texting and talking on Snapchat.

"My son Tysen Benz was an 11-year-old student, athlete, comedian, friend, brother, charismatic and all around amazing child," she was quoted as saying by a friend who set up a GoFundMe page for the family.

Shortly after 10pm, Ms Goss went to check on each of her three sons and tuck them in for bedtime. Tysen's door was locked, but she was able to open it with her key.

When she stepped inside, she realised he wasn't in his bed, but her first thought was simply that the boy was being cheeky.

"I went in and I thought he was being silly," she told the newspaper.

However, after a quick search, she found him inside his wardrobe.

"I tried to hurry up and lift him up. I was screaming. I told my oldest son to call 911. My littlest one was bawling."

In an interview with the Associated Press, she said it happened unbelievably fast.

"The whole thing happened in about 40 minutes. He was fine and then I found him."

Paramedics rushed to the family's home and managed to revive him, however, he was placed on life support for three weeks at a hospital near Detroit with no improvement.

Eventually, she had to make the heart-wrenching decision to let him go.

Ms Goss told AP her son's death was the result of "a twisted, sick joke" delivered in the form of cyber-bullying.

A 13-year-old girl has since been charged with malicious use of a telecommunication service and using a computer to commit a crime, after she faked her death during a conversation with Tysen that night.

Lawyers are yet to confirm Tysen's relationship with the teen, who has not been named, but Ms Goss believes she was his girlfriend.

"She did a prank that made it look like she killed herself and used other friends and their [social media] accounts to make it look like she killed herself ... so, he believed her and said 'I'm going to kill myself'," she told the New York Post.

She said her son had no underlying issues that would hint toward self-harm.

"He was perfectly happy and fine. There was no additional sadness that was occurring. He had tons of friends," she told the Washington Post.

"Anybody who knows him knows he's a shining star."

Where to get help:

Lifeline: 0800 543 354 (available 24/7)
Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
Youthline: 0800 376 633
Kidsline: 0800 543 754 (available 24/7)
Whatsup: 0800 942 8787 (1pm to 11pm)
Depression helpline: 0800 111 757 (available 24/7)
Rainbow Youth: (09) 376 4155
Samaritans 0800 726 666
If it is an emergency and you feel like you or someone else is at risk, call 111.