Robin Thicke isn’t the only charmer in the family.

The “Blurred Lines” crooner seemed to enjoy himself in Miami over the weekend, as he watched 3-year-old son Julian splash around with his 20-year-old girlfriend, April Love Geary.

As Thicke, 38, smiled on shore, his adorable toddler (whose mom is Thicke’s ex Paula Patton) made sure he had the leggy Geary’s fullest attention as he picked up shells from the water to show her.

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While Thicke squeezed in some alone time with his biggest (and youngest) fan, Geary flaunted her cheeky bikini for fellow beachgoers to see.

Despite the 18-year age difference, Thicke and his model girlfriend appear to be going strong, even earning the approval of Robin’s dear old dad, Alan Thicke.

“She’s lovely,” Alan Thicke, 68, told E! News earlier this summer. “We like her a lot.”

This article originally appeared in the New York Post's Page Six.

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