If you've walked, jogged or driven past Roath Park Lake in recent days, you may have come across a tree decorated with dozens of colourful pompoms.
But on closer inspection, a poignant message is also attached to its bark which explains why the distinctive artwork was created in the first place.
It reads: "This is a reminder to check on your sad and your happy friends, your outgoing AND your introverted loved ones, your married and your single colleagues, your employed and your unemployed relatives.
"Everyone and anyone can experience mental illness, even your seemingly strongest friend who you don't realise was suffering so deeply from depression.
"This space has been 'pombombed' in memory of Holly, our darling friend, wife, daughter and sister. We will never know the answers to the millions of questions such a shocking and unexpected exit from this world brings up.
"Please take a moment to take this in, start talking and even add your own pompoms.
"Join us by spreading mental health awareness by sharing a picture of this 'pombomb' and tagging @hollyspombombs".
Since it was erected, people have taken to Twitter to spread its message and urge people to start a conversation with their loved ones about mental health.
Anna Cessford started the Holly's Pombombs campaign following the death of her sister Holly Cowlam in July 2018.
Holly, who had a great passion for working with autistic children, took her own life shortly after being diagnosed with depression at the age of 28.
"If I had to write a list of everyone I knew who would take their own life, she would be rock bottom. She was the last person I thought was capable of doing something like that," said Anna.
"We had spoken a couple of times about her being sad and not sleeping, but within a week she was gone. It was a total shock to me and the rest of the family."
Anna described Holly as a "strong character" who would often put her own feelings aside to help others.
"She was someone who would listen to your own problems until the cows come home and always had a solution, but she'd rarely talk about herself and what she was going through," said Anna.
"As her big sister I'll always live with an element of guilt that I should have spotted it and known how to fix things and make everything better."
Holly, from London, who had married her childhood sweetheart Jack Cowlam just two years earlier, enjoyed her crafts and would often spend her time making things for her large extended family.
"After her funeral I felt really strongly that I wanted to do something in her memory and to being some joy to her community which had been left in tatters," Anna added.
"So on her birthday I made some pompoms and started getting everyone involved in creating them. I encouraged people on Facebook to make them to help trigger a conversation about mental health.
"They are really easy and satisfying things to make."
Since Holly's Pombombs was first launched, pombombs have appeared all over the UK and globally, with friends, family and even complete strangers putting their own spin on the decorations in countries such as Singapore, Dubai and Malaysia.
Holly's parents, John and Janey Walter, have also been playing their part in the campaign in their community in Cornwall.
"Most people have suffered with their mental health at some point, and I think this is just a really positive way of starting a conversation," Anna added.
"People may not be okay even if they seem okay, just like my sister."
The pombomb on the Lake Road East side of Roath Park Lake, was created by a school friend of Holly's, Hettie Lewis.
To find out more about 'Holly's Pombombs' go to https://www.facebook.com/hollyspombombs/ or @hollyspombombs on Twitter.
Hettie said: "This year, in what would have been Holly’s 30th year, a few of her girlfriends came together in Cardiff to toast our much-loved and missed friend and pombomb a tree in the city.
"Holly's legacy continues in spreading the word that everybody and anybody can suffer from mental illness, and if the colourful, woolly bundles of love in a very grey and stormy month can prompt even one person to reach out and get help, then they've achieved their purpose."
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