Today at her murder trial, the court heard that Ruddelle and Ngapera were drinking together at a Manurewa bar the night of the fatal incident.
Soon after the couple were dropped at Ruddelle's Manurewa home, they had an argument and she stabbed him twice in the chest using a kitchen knife with a 19cm blade.
The Crown alleged Ruddelle stabbed Ngapera with the intention of killing him or seriously wounding him.
However, the defence says that after years of domestic abuse she "knew what was coming" and used the knife to protect herself and her 14-year-old son who tried to intervene after his mother called for help.
Ruddelle's lawyer Shane Cassidy told the jury that her actions were in defence of herself and her child.
Cameron was living with his mother at the time of the alleged murder.
He had gone to bed early the night before after kickboxing training and dinner with his nephews and brother.
He woke briefly when Ruddelle and Ngapera got home.
He heard a door slam and "faint voices" then went back to sleep.
Shortly after, his teenage brother was at his bedside rousing him.
Cameron got up and went to the kitchen.
"I saw Joe lying on the floor ... he was not responsive," he said.
"I checked his airways, I checked his pulse ... couldn't find anything.
"It was then that I rang 111."
Cameron said his mother was in the room at the time.
"She was just standing there telling me to help Joe up off the floor," he recalled.
The 14-year-old was also in the room.
Cameron said his mother was "really emotional".
He had to go out into a hallway to hear instructions from the 111 operator.
The jury was then played audio of the Cameron's emergency call.
"There's been an altercation and my mum's partner's on the ground," he said, his voice shaking.
"I woke up and I heard arguing and then he was on the ground - I'm not sure what happened.
"I think my mum does [know what happened] ... but she is intoxicated.
"It might have been a knife ..."
Cameron told the operator Ngapera was not awake but he was breathing.
"He's bleeding, he's bleeding ... from his chest," he said.
Shouting and screaming can be heard in the background.
"Leave it mum, leave it, get out ... mum, get away," Cameron shouts as he is taking direction from the operator to try and stop the bleeding.
Cameron repeatedly tells his mother to "get out" and tells her the ambulance is on the way.
"You're bloody ... you're not helping, man," he says to her.
The 14-year-old can also be heard shouting "mum" and a woman's voice is heard crying out "no".
Cameron tells the operator Ngapera is no longer breathing and she gives him instructions on how to start CPR.
"If I take pressure off his chest he's gonna bleed ..." he says.
He tries to get his younger brother to hold a towel over Ngapera's wound as he starts chest compressions.
As he listened back to the call, Cameron became upset.
In the dock his mother had her head down and members of their and Ngapera's family cried in the public gallery.
"Don't give up, you're doing amazing ... there's lots of help coming," the operator tells Cameron as he keeps pumping Ngapera's chest.
Ruddelle can be heard screaming "no" and "come on" as she cries and wails hysterically.
"Please baby please. .. please come back, honey ... baby please come back...." she desperately screams.
Cameron further explained to the court that his mother was "obstructing" him as he tried to help Ngapera.
She had been trying to revive him and "get him up" when Cameron came in and called 111.
"There were instances where she would come up and tap him and try to wake him up," he explained.
"Just to try and get some sort of response from him.
"There was an instance where she was trying to perform CPR herself."
The trial continues.