She wrote: “My heart hurts and my world has just collapsed around me. My beautiful baby sister is no longer with us and I don’t know how to process it.
“I love you Kerri, you’re my best friend, we were inseparable and right now I don’t know how to fill the void. Be peaceful and hold Nan tight.”
Donaldson was a member of the dance group Kings and Queens, which in 2014 advanced to the semifinals of the eighth season of Britain’s Got Talent.
The group performed a combination of Latin songs during their audition, to which Simon Cowell made the following observation: “Over the years, we’ve had some fantastic dance groups on this show. I thought it was amazing.”
Alesha Dixon, a fellow judge, at the moment remarked, “If you don’t make it to the final, I’ll eat my arm.”
Other members of the dance troupe included Neil and Katya Jones, who would go on to become Strictly Come Dancing professional dancers.
‘Dance up there with the angels’
Supadance National League, a group that organises friendly matches between dance schools and clubs, also shared news of Donaldson’s death, posting a black and white image of her in a dance costume on social media.
Its tribute said: “The directors of the League are devastated to hear the extremely sad news of the passing of the daughter of their fellow directors Jacqui and Colin Donaldson principals of Diamond Dancecentre and on behalf of all the schools in the League send love and prayers to them, their family and dance school! RIP Kerri Anne.”
Donaldson’s cause of death was not given.
Strictly Come Dancing stars – including Neil and Katya Jones, Kevin and Joanne Clifton, Amy Dowden, and It Takes Two spin-off host Janette Manrara – have all paid tribute to the dancer.
Alongside a photo of Donaldson, Kevin Clifton wrote on Instagram: “Absolutely heartbroken. I’ve known Kerri since we were kids and she was always the loveliest girl. A friend and a dance partner.
“I’m glad we got to dance together this xmas. And that the whole cast of Strictly Ballroom got to work with you in rehearsals. RIP.”
His sister and fellow dancer, Joanne Clifton, wrote: “I have no words… This is just heartbreaking… truly devastating.
“We’ve known you and shared the dance floor with you basically all our lives… Dance up there with the angels Kerri… you beautiful dancer, you beautiful soul.”