The actress and model took to social media to share several childhood pictures of herself with her son, a few candid shots thrown in there as well.
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The resemblance between the two was quite striking to notice even then, as they both have similarly arresting facial features and bright blue eyes.
"Happy 20th Birthday to my little Princling," she captioned her post, with Damian himself responding with a series of hearts and an "I love you."
Many of her fans took to the comments to extend their wishes to the 20-year-old model as well, with several dropping heart and celebratory emojis.
One commented: "Happy birthday...Elizabeth is the most gorgeous mummy," with another even saying: "What a lucky lad to have such a lovely mother," and a third adding: "And a beautiful child at that!"
Elizabeth shared several childhood photographs of her son on his birthday
Damian posted a photograph of himself on the morning of his birthday, as he sat in front of a boat wearing nothing but a pair of shorts.
"Birrrtthday boy," he wrote, to which the Bedazzled star quickly responded with a flurry of hearts and an adoring message that read: "My beautiful boy is no longer a teen," with many others like Michelle Visage and David Furnish chiming in to wish him a happy birthday.
The mother and son share a very close relationship, strengthened even more as they've spent some time apart due to work commitments.
"I rather think I've simply been blessed with a child whose personality gels with mine," she previously told The Telegraph.
Damian shared a birthday snapshot of his own
"Given I'm a single mother and he's an only child, by default we do spend a lot of time together and we are utterly comfortable in each other's company."
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