On her Instagram Stories on Sunday (May 31), the Loose Women star, 30, posted a picture of the tot beaming with something red smudged all around his mouth.
"Did you eat mummy's lipstick, Rex?" she joked in the caption, adding, "Just trying to get ready" along with a string of laughing-crying emojis.
What did Stacey say?
In an Instagram Story shared shortly after, Stacey showed her followers that Rex - whom she affectionately calls Pickle - had gone down for a nap.
Lying on her back, Stacey said: "To the lovely Susan who messaged me to say 'You really shouldn't let your child eat lipstick'.
"Thank you so much because I genuinely was going to pick out a few shades for his lunch."
After hitting back with the sarcastic quip, the mum-of-three burst out laughing.
Little Rex has gone through some serious milestones during the coronavirus lockdown.
I genuinely was going to pick out a few shades for his lunch.
Last week, Stacey was in tears as she shared a super cute clip of the one-year-old taking his first steps.
Cheered on by his mum and dad - Stacey's partner, Joe Swash - the tot giggled and clapped his hands while tottering forward on some wobbly steps across the kitchen.
Stacey clapped and encouraged Rex to toddle towards her. Joe, smiling proudly, stood behind the baby and cheered him on.
The Loose Women presenter said that at least she and Joe could both be there for the special moment.
Stacey wrote alongside the post: "And he's off. Oh Pickle. Honestly I am sobbing. If there's one good thing to come out of these scary hard times it's mummy and daddy both being home to see this moment."
She added: "Rex we are so proud of you. Oh my goodness it feels like time is going by at the blink of an eye and you're growing so so quickly.
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