In the cute shots, Bridget, 30, the youngest child of late Republican Sen. John McCain and Cindy McCain, enjoys quality time with her niece, relaxing on the couch together and soaking up the sunshine in the backyard.
"My sister Bridget @bridgyyyyboo is the Liberty whisperer. Liberty is absolutely obsessed with her - obsessed, like didn't want to leave her side and was yelling 'Giget' all week," writes Meghan. "We are so lucky to have all this incredible girl power energy in our family. We're never leaving Arizona, I'm just going to move in with Aunt Bridget so she can charm Liberty to sleep every night. ♥️🌻🌟🌵"
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Although her sister and mother are public figures, Bridget is notoriously private about her life and often stays out of the spotlight.
For her birthday last July, Meghan shared a special tribute on Instagram for her sister, calling her a "wonderful" aunt to her daughter Liberty, whom she shares with husband Ben Domenech.
Earlier this month, Meghan shared a bittersweet photo on Instagram of her and Liberty visiting the gravesite of her dad John, who died on Aug. 25, 2018, after a lengthy treatment for brain cancer.
Meghan McCain/Instagram Meghan McCain and Liberty
"Love hard. Grieve hard. Miss you every day," she wrote in the caption of the photo, taken at the United States Naval Academy Cemetery.
"I was really back and forth about whether or not I was even going to do it, and I can't believe how obsessed with it I am," the TV personality said at the time. "I feel like the universe is laughing at me, because I was so scared of having kids and so reluctant and so on the fence about it. Even when I was pregnant I was like, 'I don't know, we'll see how this goes.' "