The family have jetted abroad over the Easter period with their brood, with the children's clothing designer sharing a small snippet inside their sun-soaked vacation.
"Beach babies," gushed the doting mum alongside a candid snap of the beach, before sharing a series of throwback childhood photos of Petal, with the last image seemingly taken during the getaway.
"Happy happy 14th birthday little Petal forever my baby girl," Jools wrote. "We love you so much. The first picture is my favourite capture ever, we were walking back from nursery my favourite time of the day.
"You were always so happy to be going home [heart-emoji] (We hardly went in as it was) and we would pick up a little treat from Primrose Bakery for after tea…
"Such happy times and memories to treasure. We can't wait to celebrate together with you today [a series of sea-themed emojis] xxx."
Fans were quick to comment, with many commenting on the similarities between the mother-and-daughter duo. "Awww happy birthday Petal! She's so like you! Sending hugs," said one, while another added: "Wow! Apple didn't fall far for this lovely one." A third post read: "She is your twin! Happy bday Petal xx."
Jools, 48, and Jamie, 47, are no doubt making the most of their free time with their children. Their two eldest daughters, Poppy, 21, and Daisy, 19, have been studying at university, and will have no doubt joined them on the trip. The couple are also parents to two sons, Buddy, 12, and six-year-old River.
They occasionally share the odd family pictures with fans – almost two weeks ago, they marked Poppy's milestone 21st birthday with a stunning set of snaps.
"To my darling Pops our little legend is now 21," she said. "I have never felt so unbelievably proud. In a large family full of chaos and noise you are calm, relaxed, sensitive and deeply thoughtful.
"You are a million wonderful things: polite, well-mannered, fiercely loyal and funny. Your writing brings me to tears as your empathy runs so deep. Pops you are one of a kind and you belong to us we are so lucky.
"Now you are a young lady with your life ahead fly free little birdie (just don't get a nose piercing or go on Love Island… otherwise you are free but remember I am still the boss)."
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