The star - who plays Fiz in the ITV soap - announced her happy baby news via Twitter on Monday evening (1 December), writing: "On Saturday our lives changed forever with the arrival of our baby boy Albert. Happiness and pride like never before x."
Jennie, 30, was inundated by congratulatory messages from fans and co-stars including Natalie Gumede, Chris Bisson and Paula Lane.
Paula, who is expecting her first child, tweeted: "Aaw Jennie I could cry! Albert!!! Congrats to you and Chris lots and lots of love xxxxxx."
And co-star Antony Cotton tweeted: "Waited since Saturday to share @jenniemcalpine and @ChrisFarr1's wonderful news - Baby Albert is finally here. I love him already!"
Jennie and her partner Chris announced the pregnancy back in May.
At the time, Jennie said: "We have some news to share. Chris and I are expecting an addition to our family. Very happy x."
The couple have been together for nine years and co-own a restaurant, Annies, in Manchester.
Stars who welcomed babies in 2014!
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