Yvonne Valentine thought her son had moved out when she popped over to the home of his long-time partner around Christmas time. The pair shared a drink, but little did she know her son was buried a few feet away in the back garden. How did a primary school teacher become a killer and how was her crime uncovered?

Nicholas Billingham had been in a relationship with Fiona Beal, a well-liked Year 6 teacher at Northampton’s Eastfield Academy, since about 2004.

But in late 2021 his mum received what she described as a “really long text” from his phone, which was “a bit unusual for Nick”.

The message said he had just come out of a football match at Manchester United’s ground, he was living in Essex and working with cars.

It went on to say he was now in a relationship with someone call Faye and “I know you must think of me… but I’m really happy”.

Fiona said: “I left it at that and said, ‘well as long as you’re happy Nick’, which I was more concerned about.”

The message was not from Nick.

Prosecutors told Beal’s first crown court trial that she used his phone to send messages to friends and work colleagues, pretending that he was still alive.

She had, in fact, stabbed Nick in the neck and buried him in the garden of the home they shared in Moore Street, Northampton, under a mound of bark chippings and building materials.

Beal had told the school she had tested positive for Covid-19 and she was absent from work between 1 and 12 November 2021.

On 13 November, she was caught on CCTV in a B&Q, being helped by a member of staff with two trollies carrying bags of compost and stones and a light-coloured plastic planter.

When she returned to work she said her partner had left her, but there were no concerns about her performance.

Unaware her son had been killed by Beal, Yvonne went over to the home.

“Fiona offered me a Christmas drink. I said, ‘oh thank you’. So we sat there with this drink,” she said.

“But then it always gets to me because I think Nick was buried in the garden just a few feet away and I didn’t know he was there. It just seemed normal, like I’d been to visit them before.”

Looking back, she tries not to think about it too much “but when I do it just, it’s sort of draining – it’s horrible to think of how she buried him”.

“How you could hate somebody that much to do what she did? I thought she loved him.”

It was not until March 2022 when Yvonne received a call from Northamptonshire Police to inform her Nick was a missing person.

“And I said, ‘what?’ I couldn’t believe it, just couldn’t believe it,” she said.

Police had become involved after Beal was absent from work.

She was detained under the Mental Health Act when officers traced her to a rented lodge in Cumbria.

A notebook found there said: “I thought about leaving but the things he said and did fuelled my dark side – I call her Tulip22, she’s reckless, fearless and efficient. Ruthless.”

It later added: “I got him to wear an eye mask. It was harder than I thought it would be. Hiding a body was bad. Moving a body is much more difficult than it looks on TV.”

Beal claimed in the notebook she had been spat on and threatened during sex, and subjected to cruel and belittling treatment.

Yvonne said her son “wasn’t an angel. I don’t think I know anybody who is an angel”.

“He had his moments like we all do I suppose. He wasn’t an angel but I don’t think he was a devil either,” she said.

In Beal’s first crown court trial, she accepted the killing but denied murder, with her defence team stating she had been manipulated by the “psychologically domineering” Nick to the point where she was “broken”.

But that original trial collapsed after a legal error, when it emerged a key defence witness was a court custody officer who had conducted welfare checks on Beal.

Shortly into her retrial at the Old Bailey on Friday, Beal changed her plea, admitting murder. She is due to be sentenced next month.

Speaking last year while the first trial was ongoing, Yvonne said: “I still expect to bump into Nick somewhere, you know, up the high street or in a pub or somewhere and I’m sure his friends probably do as well.

“But I think we’ll just have to try and move on. Nick’s always there in my heart.”

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