Kerry Katona waved goodbye to her daughter Molly as she moved to Ireland to live with her grandparents to study to become a surgeon.
Molly is celebrating her 16th birthday today but is away from her mum for the first time.
The teenager sent an emotional message to Kerry, 36, thanking her for “sacrificing everything to be a mother” to her.
Read more: Cheryl makes big decision about her return to The X Factor
The text message read: “Mum, the past 16 years you have sacrificed everything to be a mother, you always told me something changes when you become a mother and your whole life changes.
“Today on my 16th birthday I am also celebrating you for being the best mother I could have asked for.”
She added: “Here’s to you mum and also you’re welcome for having such an amazing first born.”
Continuing her heartwarming message Molly praised her mum saying: “Don’t forget I may not be there physically right this very moment but I’ll always be right there with you.
“I’ll see you soon, love your favourite (don’t lie we all know it’s true).”
An emotional Kerry captioned the post: “Oh my god I’m in bits!!!!!!!!! My baby girl sent me this today on her birthday 😘 my god I miss her sooooo much 😘.”
Fans praised Molly for her “beautiful” words as one commented: “What a beautiful text, be amazingly proud of yourself as a mother.”
Another said: “What a beautiful thing to say Kerry you must be so proud.”
“Oh my God this is beautiful, what an amazing, thoughtful daughter you have,” a third wrote.
Earlier this year it was revealed that Molly would be moving to Ireland to be away from showbizzy distractions and focus on her dream to become a surgeon.
Kerry shares Molly with ex-husband Brian McFadden. They also have 14-year-old Lilly-Sue.
Speaking to OK! magazine the former Westlife star said: “My oldest is going to school in Dublin in September, so she’s probably going to live with my mum and dad.
“I think it’ll be easier for Molly to concentrate on her exams there. It’s going to make things harder now for us all to be together, but you have to make sacrifices.”
Praising his daughters Brian, 37, recently told This Morning: “They’re such great kids. They’ve obviously had it hard what with me and Kerry breaking up when they were very very young.
“But with what they’ve gone through – they’re just such amazing kids.”
“Kerry’s done a fantastic job raising them.”
Last week former Atomic Kitten singer Kerry poured her heart out in a video on social media begging Molly not to “abandon” her.
She said: “My baby girl having cuddles with Mummy tonight. I don’t want her to leave me!”
https://www.instagram.com/p/BYJ1WZRA4EZ/?hl=en&taken-by=kerrykatona7
Read more: Nicole Scherzinger hits back at Louis Walsh’s outrageous claims
As she fights back tears, she repeats: “Don’t leave me! Don’t leave me, Molly!”
Off-screen, the teenager tries to reassure her mother, but Kerry sobs: “She’s abandoning me!”
The Cheshire-born star briefly manages to pull herself together, telling viewers: “I am joking… but I’m absolutely heartbroken.”
And then she’s off again, crying: “Don’t leave me, Molly. I’ve got abandonment issues!”