Pregnant Ivanka Trump poses with her kids in sweet family photo after Donald Trump's big primary win

Ivanka Trump had plenty of reasons to celebrate over the weekend.

The gorgeous businesswoman tweeted a cute picture of herself and her kids -- 4-year-old daughter Arabella Rose Kushner and 2-year-old son Joseph Frederick Kushner -- on Sunday, after her father, presidential hopeful Donald Trump, clinched a big win in South Carolina's primary.

"Happy Sunday!" Ivanka wrote, smiling big and showing off her pregnancy glow. The 34-year-old stylish star is currently expecting her third child with her husband, real estate developer Jared Kushner.

SEE MORE: Chelsea Clinton and Ivanka Trump Are Basically Besties Despite Their Parents' Rivalry

The adorably pregnant mother of two revealed to ET in November that her third pregnancy has been the easiest yet.

"I feel really good," she shared. "My two little ones and both of my roles at [the] Trump [Organization] and my own brand have kept me very busy, so it's somehow easier with the third. You're almost too busy."

"You do kind of forget about it," she added. "I have to remind myself when I want that coffee in the morning."

Trump's commanding victory on Saturday night marked his second primary win, the first being in New Hampshire earlier this month. The former Apprentice star is now widely considered the front-runner for the Republican presidential nomination.

Ivanka Trump through the years:

In December, Ivanka talked about her dad's headline-making presidential run, and admitted that she doesn't always side with his controversial politics.

"Well, I'm his daughter. In a political capacity, I don't [admonish him]," she told Town & Country. "It's his campaign. I don't feel that's my role. But I would challenge him as a child. That's what children do. [My daughter] Arabella challenges me every day. People ask me, do I ever disagree with my father? It would be a little strange if I didn't."

Still, she of course fully supports the 69-year-old billionaire's campaign.

"It's amazing to see how his message has resonated and what he's been able to accomplish as a non-politician with a very strong point of view," she said. "He's my father and I love him and I fully support him. I'm always there for him if it's helpful."

SEE MORE: EXCLUSIVE -- Megyn Kelly Tells Touching Story About Donald Trump That Speaks 'Beautifully' of Him

Earlier this month, Time magazine's Jay Newton suggested to ET that Ivanka's likeability is a big factor in Trump's recent victories.

"Ivanka definitely helped Trump win in New Hampshire," Newton claimed. "She's likable, she's beautiful, she's out here, 8-9 months pregnant campaigning for her father."

"She speaks passionately about what a great guy he is," he added. "That really humanizes him with women."

Watch below: