Sarah Bartlett, from Sidcup, Maidstone, was touched by the message in the card - which also came with a generous £100 in cash slipped inside it!
Initially thinking it was a note wishing her a belated happy birthday, the 37-year-old was shocked to read the following message inside:
"Darling Sarah, from another mummy who has noticed that you do an amazing job, enjoy the enclosed, for you. Be blessed."
Sarah, who has three children - Holly, 17, Ben, 10, and Georgia, five - explained the entire gesture left her in tears of happiness.
"When I opened it, I started to cry with happiness. I am just so grateful and cannot thank them enough.
"It’s not all about the money, it’s the gesture which made me feel so incredibly happy. It made my week.
"It’s not every day something like that happens – I’ve never experienced anything like this before."
Although the random act of kindness happened last weekend, the touched mum still doesn't know who her mystery admirer is - all she does know is that they're "kind-hearted and selfless."
She says she has asked around all her friends, but none of them have fessed-up to the good deed.
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