The former EastEnders cast member, 29, took to social media earlier to share photos from her celebrations, which included her young daughters Ella, seven, and Mia, three.
She posted photos on Instagram earlier which showed the three of them in an outdoor area that had been decorated with red, white and blue balloons for the royal milestone.
Jac - whose husband Dan Osborne, 30, was absent from the photos - kept to the theme of the occasion with her opting to wear a blue dress, red lipstick and white footwear.
The I'm a Celebrity alum was the queen of the family, with her sporting a homemade crown for the occasion - which featured jewels and read "mummy" across the front.
Her daughters - who posed with grandmother Selina Jossa in one photo - wore matching red and white outfits, with bows in their hair matching the colours of the Union Jack.
Lucy Mecklenburgh, 30, and Ryan Thomas, 37, took the opportunity to celebrate the Platinum Jubilee at a street party instead, attending with their two young children.
The couple went with their son Roman, two, and their newborn daughter, whose name has yet to be announced - with the pair both posting about the visit on Instagram.
The Only Way is Essex alum Lucy shared photos of Roman - in a striped jumper and navy pants - at the party, with him posing in front of a large Union Jack flag in one.
She also shared a photo of her daughter in a pram, with a jubilee flag nearby. Lucy later shared footage of Roman outside a door that featured a jubilee themed balloon arch.
Ryan posted a photo of Lucy and son Roman sat together at the street party, with the youngster on his mum's knee whilst sporting a Union Jack-themed plastic hat.
And another celebrity who marked the special occasion was reality TV star Dani Dyer, who enjoyed a garden party with her son Santiago, one, and her "bestie" Kayleigh Short.
The Love Island alum, 25, went casual for the party, with photos showing in a pale orange top, denim jeans and a pair of white trainers - accessorised with a some sunglasses.
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The outdoor setting had been decorated with a balloon arch and other themed decor, with Dani and pal Kayleigh posing with cans of gin and tonic whilst at the party earlier.
Dani also posted a photo of her son Santiago - who she shares with ex-boyfriend Sammy Kimmence - sat on a picnic chair, with him wearing grey dungarees.
Lydia Bright, 31, also embraced the jubilee weekend with the reality TV star giving fans a glimpse inside her celebrations earlier with a video that she uploaded to Instagram.
It showed her daughter Loretta, two, sat in an outbuilding which had been covered in Union Jack merchandise including bunting, flags and hats to mark the jubilee.
The TOWIE alum toured the back of the room, showing fans an extensive buffet of party food for the occasion - including scones, sausage rolls and strawberries.
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