Proud mum Kerry uploaded a video of her eldest daughter singing and playing the ukulele onto her YouTube account.
"Mother, you're still young to me," sings the teen.
"So please stop pretending, you're older than you'll be.
"Because mother, you're beautiful and cool.
All the parents drool,
When you strut your stuff through the school.
"My mother, it's your birthday today,
You're 34 say... and you're not even grey!
"So mother, happy birthday to you.
I found a couple of care homes but you've got another year or two!"
Story continues below the video
Kerry has two daughters with her first husband Brian: 13-year-old Molly and 11-year-old Lilly-Sue.
She also has seven-year-old Heidi and two-year-old Max with her second husband Mark Croft, and in April she gave birth to Dylan-Jorge (DJ), her first child with husband George Kay.
It's been a busy month for the family: Molly turned 13 on August 31, Kerry celebrated her 34th birthday on September 6, and Kerry and George got married on September 14.
Molly's father, Brain, is now married to model Vogue Williams.
Vogue recently spoke about how her relationship with Brian's daughters has improved since she and Brian moved back to London, after living in Australia.
"We would go home every six months to see the kids, but then we would have them for six weeks," Vogue told the Independent.ie. "We see them a lot more now, which is great.
"Molly is nearly the same height as me now," she adds. "I just can't believe that Brian has a teenage daughter - it's like he has lived two lifetimes."
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