'Today. So happy my all day nausea is finally easing up!' she wrote in the caption along with the hashtags: 'Jeans won't button up' and 'here we go.'
Several Australian celebrities rushed to offer Jennifer some words of wisdom.
'You need to do the hair tie on the top button trick,' model, Megan Gale wrote.
The Project host, Carrie Bickmore commented: '(Morning sickness) is the actual worst! Just keep your eye on the cute squishy prize at the end.'
The 35-year-old announced she's expecting her first child with husband Jake Wall earlier this month.
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