``Has he come over for dinner?'' Mrs McGinty asked.

``Yes, he has,'' came Mrs Speering's reply.

Mrs McGinty heard her lifelong friend say ``Open the door'' and Trent say hello to his mum.

But NSW Ambulance Service paramedic Trent Michael Speering was not at his 72-year-old mother's Baulkham Hills home on June 11 in order to have dinner. He went to kill.

The paramedic, suspended from duties at Springwood station, had been in dispute with the ambulance service, having complained of being bullied and condemned by senior management as ``vermin''.

He believed he was to be sacked and, tormented, decided to kill himself and take his mother with him.

Police sources said Speering, 40, shot his mother in the back of the head as she prepared his dinner then placed her head on a pillow, covered her with a blanket as she lay on the kitchen floor and shot himself.

Mrs McGinty said: ``They were devoted to each other.

``He was her only child.

``Why didn't his bosses get him help or counselling? He was obviously in trouble.

``His mother would have definitely done something if she knew.''

A friend, Jan Van Dyke, said: ``Monica was a very social woman who held an important position on Baulkham Hills Council for many years.

``She was a member of National Seniors [association], the local theatre group Castle Hill Players and Probus. I want some answers.

``It was obvious this lad was crying out for help.''

Hours before the murder-suicide, Trent sent a stream of letters to the media, relatives and the ambulance service.

``As hard as it will be, my intention is to kill my mother,'' he wrote.

``I don't want to leave her behind as there would be no one to look after her as she got older.

``Then I'll kill myself.''