A member of the group came up with the idea of people donating small amounts of money to the Murphys for a scooter, while another member, Elaine McNabb, is collecting the money and organising for a replacement scooter.
Matt, 12, wanted nothing more than an MGP scooter for Christmas, and he was delighted when he received one.
However, it was faulty, so his parents ordered a replacement, which arrived last Sunday.
The next day, Matt was taking part in a YMCA programme at Lorenzdale Park, in Gonville, and had his precious new scooter padlocked up.
"My friends wanted to borrow it, so they did, and they told me they'd put it down over there, but when I looked it had gone," Matt said. "They had only put it down about a minute before."
He said a lot of people were at the park but there was no sign of the missing scooter, although he searched for about half an hour.
"I was really annoyed. It was such a cool scooter," Matt said.
Mrs Murphy said she was angry at the theft but amazed at the response on Facebook when strangers started donating money.
She moved to Wanganui a year ago to be closer to her son and has struggled to feel at home in the city.
"I know no one here and have never felt so alone in my life" Mrs Murphy said.
"But at times I have been in tears because of the support and kind words written on Facebook. For the first time, I am pleased I have moved here."
She said she could not accept the money, so Ms McNabb had done so and would buy a scooter and give it to Matt.
Money left over would be donated to the Toy Library.
Ms McNabb said she was proud of how the Facebook group members had responded to Matt's plight, although she said it wasn't the first time such a thing had happened.
"A lot of people seem to have been having things stolen, but so many people are willing to help others out," she said.
