A mother killed her five-year-old son and then tried to take her own life after the 'challenges of caring for him' made her depressed, a court has heard.
Claire Button, 35, has pleaded guilty to the manslaughter of her child Lincoln Brookes at their family home, but denies murdering him.
They were discovered at the house in Windstar Drive, South Ockendon, Essex, on December 15 by Button's husband and Lincoln's father, Nicky, when he came home from work.
Lincoln, who had been diagnosed with autism, was pronounced dead at the scene.
Jurors at Basildon Crown Court were told during the murder trial that Button had been accused of smothering her little boy before placing a note beside his body which read: 'DNR - do not resuscitate.'
Another note left in the property, allegedly written by Button, said: 'He [Lincoln] does not fit in the world and where he doesn't fit I don't either.'
Andrew Jackson, prosecuting, told the court that 'what happened that day was a deliberate and unlawful act plainly done with the intention of killing Lincoln'.
'It appears that the challenges of caring for an autistic child had caused the defendant to become depressed and she chose to murder her child,' Mr Jackson said.
The court was told that Lincoln was a physically healthy boy and 'loved' going to the mainstream school that he attended.
Jurors were told that Lincoln lived at home with his mother and father.
Button's mother lived nearby and was 'part of a large network of family support' and had even qualified as a carer so that she could help look after Lincoln.
During the school summer holidays in 2024 Button was taken by her mother to a mental health unit at Basildon Hospital, where she was diagnosed with depression and given medication.
The medication 'appeared to be having a positive effect' after a week and by the time Lincoln returned to school things had become better.
But the October half-term break 'marked a return to the problems'. Button visited her GP and was prescribed an increase of the medication given to her for her depression. Her condition again improved once Lincoln was back at school, Mr Jackson said.
The prosecutor added: '[With] the school Christmas holidays on the near horizon the defendant was again saying that her health had deteriorated.'
Jurors were shown footage of Lincoln and his mother entering a Lidl supermarket on December 14, a day before he was killed.
The youngster appeared fixated on the store's automatic entrance door, being filmed going to and from them multiple times.
The following day Button briefly visited her mother with Lincoln. During the visit she told her about what happened at the supermarket.
At 11.25am that same day, December 15, the defendant made a call to emergency services where she asked for an ambulance. She reported to the call handler that 'she was about to take an overdose'.
Button, who was at home with her son, was asked if she was with anyone and she replied that it was just her alone. The 999 handler advised Button to wait with a friend as they 'might not be able to get an ambulance to her for 10 hours'.
Button's husband made the tragic discovery about his son when he returned home from work just before 3pm on December 15.
Paramedics were rushed to the scene but Lincoln was declared deceased at 3.55pm.
Button was taken to hospital after suffering injuries and telling medics that she had taken an overdose. She was later arrested by police officers on suspicion of murder.
The trial at Basildon Crown Court continues.