Her mother Evelyn Ryan, who was a well-known pianist with a music degree who taught music in Wellington, suggested Bonnie take the initiative and perform on the street.
"It was at my mum's advice. Mum said 'why don't you get a keyboard Bonnie and set up on the street and go busking'," she said.
"It would fit in with me while the kids were at school."
Bonnie said she bought her first keyboard from a music shop in Wellington and taught herself how to put a beat and chord changes into the background so she could finger along in time.
She had learnt more than 100 songs and played by memory. Her favourite was When Irish Eyes Are Smiling, while she always made a point of playing Amazing Grace.
"I don't know why. I just love that song," she said.
"I don't even need to think about it. It's all second nature now. When I first started I used to practise for hours at night when the kids were in bed to get the timing right to fit the music and the chord changes."
It is a distinctive style for which she had become famed around Levin. She had also played in church.
Bonnie could now play her Casio for two or three hours at a time, although the very first time she busked was only for 10 minutes.
"I looked down and I had $5. I couldn't believe it," she said.
So how much money can a busker make?
"Each day is different. Sometimes it's $5 or $10, sometimes its $50. There's no rhyme nor reason. Yesterday it was $13," she said.
Bonnie had never been given a $100 note, although she had twice been given a $50 note, one from a handsome gentleman who had stopped for a chat.
"He stopped and asked me what I was doing this for, and I said for my daughter's ballet dancing classes," she said.
"He wrote me a cheque for $50. I don't know who he was. My daughter did ballet dancing for eight years."
Crighton said she was proud of how her children had grown up.
"I am so proud," she said.
"I don't regret any of it. I brought my kids up better than I had wanted to. I couldn't be more proud of them. They all got higher education."
Bonnie now has three grandchildren, although none were showing an interest in piano - yet.
"I tried to teach my kids but it wasn't easy and so I just encouraged them to do what they wanted to do," she said.
Bonnie originally began busking at the back of the old Levin Mall where the town library now stands, but she was asked to move on one day when trouble erupted.
"Someone else was busking there and they began intimidating someone that was getting money out of the money machine, and ever since that happened they stopped people busking out the back," she said.
There were other occasions when busking etiquette fell short. One fellow busker would kick her money box every time he walked past, while once she was verbally intimidated by a another busker.
"It was horrible. He was in my face and people had to step in," she said.
"And one day someone said to me 'why don't you go home and do housework'."
"But generally people are so good. People say to me 'you're cheering up the street', or 'it's good to have you here', or 'that sounds happy', and it's all very positive, which overrules the negative."
Bonnie had seen many changes to the main street in the last 30 years. Shops had come and gone, buildings had been torn down and replaced, and there was certainly more traffic.
While she played in Levin at least twice a week, when Bonnie felt like a change she would drive to another town, or to a camping ground in the summer.
"If it gets too cold I have to get up and go," she said.
Has Bonnie ever thought about singing along too?
"No, I can't sing. I've got an awful voice. I don't like the sound of my own voice even. I wish I could sing though," she said.
"Who knows, I might have made it to Broadway. I might have got discovered and put in the movies. I often think that why doesn't someone give me my big break. I'm always open to someone discovering me."
