Ms Seymour's mother Wendy Bowler, 60, of Bedfordshire, said her daughter told her they were feeling unwell, and that they were going to try to sleep it off.
Natalie Seymour and her friend Abbey Amisola - aged 27 from Winnipeg, Canada - are said to have been found unresponsive this morning in their room by a member of staff at the Monkey Republic guesthouse, a backpacker in hostel Kampot.
Cambodian officials claimed they had been suffering from severe vomiting and diarrhoea. "Our thoughts and prayers go out to Abbey's family and those who knew her", Norm Gould, president of the teachers' society, said in an emailed statement.
Her body was found alongside that of friend Abbey Gail Amisola, 27, from Canada - but what do we know about their tragic deaths?
It is believed Ms Seymour and Ms Amisola were found by a shocked member of staff and were quickly rushed from the backpackers' hostel to a nearby hospital, but they couldn't be revived.
Adding, 'They chose to sleep it off but never woke up again, or that's what I hoped.
Mobile's Black Friday deals start November 17
And each time, as a cherry on top, they offer massive price-cut on other things offered as well. The list of devices includes the Samsung Galaxy S8 , Galaxy S8 Plus and the Galaxy Note 8 .
Seymour had a passion for traveling and met her Canadian friend while visiting Bali previous year noted the nypost.
Natalie had posted pictures to her social media account just three days ago when she visited the idyllic island of Koh Thonsáy.
'She told us everyday where she was going to be going and what she was going to be doing, she always really wanted to travel and just wanted a break from work'. "This is now in the hands of the police, but there is nothing suspicious about their deaths".
"Abbey was the light of our family and her friends, as well as a devoted and loved high school teacher", the unnamed relative said. A spokesman for the hostel said that the staff were "devastated" by the tragedy.
"The local police are investigating possible causes, and we're respecting the privacy of the women's families, who are in contact with the British and Canadian embassies".
The federal government said a Canadian citizen had died in Cambodia, but would not release details or confirm the citizen's identity, citing privacy laws.