A police officer who picked up a family that had broken down on the M4 bought them Christmas presents after hearing they had none.
Midwife Rhiannon Williams, 37, saw the officer in Tesco at Culverhouse Cross, Cardiff, at about 04:00 GMT.
She said the family, including three children, "weren't going to be getting much of a Christmas at all, so she thought she'd do something about that".
South Wales Police Supt Alun Morgan called it: "A story to warm the heart."
Miss Williams, who lives in Barry, Vale of Glamorgan, was in the supermarket in the early hours to avoid the Christmas rush and got chatting to the uniformed officer after spotting her "with a stack of presents under her arm".
She said after taking the family home to Cardiff following a break-down on the M4, the officer realised they did not have any gifts.
"So she spent her own money to give them a bit of a surprise, which I thought was really sweet - it was a lovely token of humanity," she added.
In her Facebook post praising the officer, Miss Williams said a Tesco manager heard about her generosity and offered to donate more gifts.
"Was a really lush moment," she wrote.
In a Facebook post, South Wales Police said: "The officer visited Tesco Culverhouse Cross to buy them some goodies for Christmas.
"Staff at Tesco found out about the amazing generosity of this officer and they have contacted us wishing to also donate some amazing gifts for the whole family.
"These gifts including all the ingredients for the best Christmas dinner will be delivered by SWP officers this evening! Merry Christmas from all at South Wales Police!"