The Irish singer - who has five-month-old daughter Anaíya with fiancé Jason Bell - congratulated her former Girls Aloud bandmate on her shock marriage to Jean-Bernard Fernandez-Versini and advised her to start a family as soon as possible.
She tweeted: ''Aww @CherylOfficial you must be having an amazing time. I am so happy for you! Good luck with everything. Come join the baby club. Best ever (sic)''
Cheryl replied with a string of emoticon faces blowing kisses.
Meanwhile, following claims from her new husband's friend Curtis Jones that the club owner is a womaniser who can't be tamed, the 'Crazy, Stupid Love' hitmaker has issued a tongue-in-cheek response.
She posted a black and white Instagram picture of herself smoking with a quote printed over it which read: ''I hear you're a player. Nice to meet you. I'm the coach.''
Cheryl - who announced earlier this week she had married Jean-Bernard last week after two months of dating - also found the time to thank some of her former 'X Factor' mentees for their messages of support.
Rebecca Ferguson - who is pregnant with her third child - said: ''it's nice to see you have found happiness and peace congratulations x''
Cheryl replied: ''thank you babe. I hope everything is going well in your pregnancy''
And she offered a simple ''thank you'' to Cher Lloyd, who had said: ''Congratulations!!! Wishing you both all the best!!!(sic)''
The BBC drama starring Aidan Turner returns to BBC One on September 4th.