Liam posted the video to his Twitter page.
In the video Liam says: "Hey Cath, good luck on Strictly Come Dancing. Everyone here at Coronation Street is missing you.
Hey Cath, good luck on Strictly Come Dancing. Everyone here at Coronation Street is missing you.
"Keep on dancing."
Cath, 36 is partnered with Strictly professional Johannes Radebe and said she was "beyond thrilled" to have been kept in by the public after the first live vote this weekend.
Catherine left the cobbles last year after her character Eva Price decided to depart with baby daughter Susie.
Since leaving the soap, Catherine has been starring in new BBC sitcom Scarborough.
Earlier this month, Catherine's son Alfie melted herts as he wished his mum and her Strictly partner Johannes good luck.
In the video, Cath's husband asks Alfie: "What do you want to say to Mummy and Johannes?"
The youngster replies enthusiastically: "Good luck Mummy and Johannes!"
Tom then asks him, "Are you excited? Will you be watching?" and he squeals, "Yeah!"
With encouragement from his dad, Alfie adds: "Keep dancing!"
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