Blake Lively Took Her Niece Kate, 19, on a Tiffany & Co. Date Night — and They Were Both 'So Well Sparkled'

Blake Lively took one a special date with her to Tiffany's!

Earlier this month, the Gossip Girl alum, 36, fêted Tiffany & Co.'s Tiffany Titan by Pharrell Williams collection launch at the jeweler's New York City flagship store on May 2. 

While it looked like she went solo at the time, Lively revealed that her 19-year-old niece Kate Johnson (whose mom is Lively's sister Robyn Lively) was her plus-one.

In a new Instagram post shared on May 10, the Betty Buzz founder included two selfies of her and Johnson in their sparkly outfits. 

“When you dress up as just the tail.  Thank you @tiffanyandco for having me and my angel niece @cakey.johnson We felt so special. So well fed. And so well sparkled,” Lively wrote.

Lively wore a mermaid-like beaded turquoise dress from Happy Isles. The number matched perfectly with her Tiffany & Co. bling, including a platinum necklace with a blue cuprian elbaite tourmaline of more than 12 carats on a diamond chain wrapped around her wrist like a bracelet.

She also decked out her look with diamond bird brooches boasting over 28 carats, as well as diamond earrings and stacks of rings (which you can see in a close-up shot in Lively’s photo dump). 

Johnson dazzled in a bejeweled blazer that jazzed up her black V-neck dress and pillowy heels. Like her aunt, the teen wore a pair of eye-catching statement earrings. 

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One selfie also shows the two with beaming smiles and basking in the fun of the party, which brought a coterie of Tiffany & Co. muses to The Landmark. 

Lively didn’t forget to introduce her relative to a few of the A-list guests, including Rosalía. Inside, the three posed for a photo, with Lively and Johnson on either side of the “Beso” singer, who wore a black off-the-shoulder gown with ruffles and a thigh-high slit.

In addition to Kate, Robyn shares sons Baylen, 21, and Wyatt, 16, with husband Bart Johnson. Lively shares daughters James, 9, Inez, 7, and Betty, 4, with husband Ryan Reynolds. The couple quietly welcomed their fourth child earlier this year, and they have yet to reveal the sex and name of their newborn.