Murder in Massachusetts! Motive?

What causes a person to decide to murder
their spouse and children?
The recent case of the Briton whose American wife and
child were shot dead in their home in the USA while it
is believed he was enroute to the UK. I find it hard to
accept the death which appears to have no motive as yet.
Is it life Insurance?
The rent on the house seems awfully large and there does
not seem to be a money trail?
Is it another woman?
Mr. Entwistle actions are indeed suspect to me.
Where is this woman's family?.
Who ever did this did it cleverly!
But I have faith in our American justice system and feel
they will get a time of death soon.
I am willing to bet Friday. HMMM
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Neil Entwistle, voluntarily went to the US embassy, and was
questioned about the deaths at their home.
Rachel Entwistle, 27, and baby Lillian, nine months, were found
at their home in Hopkinton, Massachusetts, on Sunday.
Mrs Entwistle taught drama and English at St Augustine's
Catholic School in Redditch, Worcs, between 2002 and 2005.

US police had already spoken to Mr Entwistle on the phone
following the discovery of his wife and child.
The 27-year-old is thought to have left the US before the bodies
of his wife Rachel and daughter Lillian were discovered under a
pile of blankets in a bedroom at their home.
Mrs Entwistle had been shot in the head, Lillian in the body,
at some time between last Friday morning and Saturday night.
Mr Entwistle, from Worksop, Nottinghamshire, is believed to
have boarded a flight from Boston to London on Friday.
The family had only lived at the address for 10 days.
Party plans
They were reportedly due to host a dinner party on Saturday
night, but when guests arrived, it appeared that no-one was at
home.
It has emerged that officers went to the house that night after
being contacted by Mrs Entwistle's mother and stepfather
and entered the bedroom where the bodies were eventually
found, but only saw what appeared to be an unmade bed.
And it was only when police returned on Sunday that police
noticed an odour which suggested there might be bodies in
the room and discovered them under the bedding.

Full Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/uk_news/4654448.stm