"Christmas presents and other household items appear to have been the target of this burglary, with several items abandoned and strewn on the lawn," police said in a release.
The family are now staying with friends as they go through the arduous task of insurance claims during the holiday period. This was not the first house fire they had suffered - their first home in Nixon Street was set alight by an electrical fault not long after they arrived from England at the end of August.
"When I received a call from police on Monday morning saying something about a fire, I was confused," Mrs Shemwell said yesterday.
"I thought they must have been talking about the Nixon Street fire, and then it dawned on me. That fire happened just eight days after we moved in, but it was mostly smoke damage and we didn't lose much at all."
They were moved into the Acacia Park Motel in Anzac Parade after the first fire, but that was around the time of the floods. "We got moved into another motel unit just before midnight after emergency staff said they feared the Whanganui River would burst its banks," Mr Shemwell said. "It all ended okay, though, and then we found the Kells Avenue house and moved in."
The family lost most of their possessions in Monday's fire.
Wrapped presents sent by Mrs Shemwell's family in Britain were a target for the thieves. "The burglars put them in a bag and then, for some reason, dropped them on the front lawn when they fled," Mrs Shemwell said.
"We managed to rewrap them and opened them this morning in front of my family on Skype - it was quite emotional."
The family are staunch Christians and says the trio of ordeals over the past few months only strengthen their resolve. It certainly has been an emotional time and difficult to process, but what has come from the ordeals is an overwhelming sense of community spirit in Wanganui, Mr Shemwell said.
"We are absolutely amazed that complete strangers are offering help. Tasha and I are Christians and we praise God for this help."
Mrs Shemwell said she and her husband were also praying for the perpetrators of Monday's incident.
"Tasha is the one working and I'm not after paid employment at this time," Mr Shemwell said. "I'm here to volunteer and help people and, through my work, I know there are some out there who have had difficult upbringings."
Appeal lifts spirits
Sean and Tasha Shemwell have been moved by the way people have rallied around them since fire ravaged their home on Monday.
Cleveland Funeral Home has offered a donation to help them get back on their feet, and Wanganui woman Kelly - who doesn't want her last name used - has started an appeal.
"I do not know the family, but it's Christmas, and they deserve to have a good one," said Kelly who is asking for donations of goods, including clothes and toys.
Anyone who wishes to donate can contact Kelly on 027 5818531, and donations can also be dropped off at the Central Baptist Church.