The maverick senator from Arizona is (almost) another year older.
In photos posted over the weekend by both women, the senator could be seen blowing out the candles on a special birthday cake in his home state.
“An early 81st birthday! Happy Birthday to my love! @senjohnmccain,” wrote Cindy on Instagram.
Of her own image, Meghan wrote, “Happy early birthday Dad – I love you with all my heart.”
Earlier this month, McCain completed his first round of chemotherapy in fight against brain cancer. McCain has been receiving treatment at the Mayo Clinic in Minnesota after doctors discovered a malignant brain tumor earlier this year.
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Amid news of his health crisis, McCain has stayed positive – and thanked Americans for the ongoing support.
“Thanks for your letters, thanks for your phone calls, thanks for your outpouring of affection,” McCain said in a brief video obtained by NBC News in early August. “Even those that want me to die don’t want me to die right away, so that’s good.”
“Overall, I just want to say thank you. Thank you for your friendship, thank you for your loyalty, thank you for everything you’ve done for literally the luckiest guy on Earth,” he added.