Chelsea Clinton Shares Throwback Halloween Photo for Mom Hillary's 74th Birthday

Chelsea Clinton/Twitter

Chelsea Clinton sent a sweet message to her mom, Hillary Clinton, on the former first lady's 74th birthday Tuesday, adding a throwback picture of the pair clowning around.

"Thank you Mom for being a clown with me for Halloween, supporting all other costume choices throughout the years and always cheering me on," Chelsea, 41, wrote on Twitter. "Most of all, thank you for being such a wonderful grandma. Happy Birthday @HillaryClinton."

While her daughter was looking back at their colorful Halloween costumes, Hillary was across the pond at the University of Oxford also thinking about the past.

"A quarter century ago, when I declared in Beijing that human rights are women's rights and that women's rights are human rights once and for all, it was viewed as a controversial statement. Now it's a feminist rallying cry," she said at an event called Women's History: The Future.

The former senator and secretary of state also spoke about running for president in the U.S. against Donald Trump in the 2016 election.

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"As a candidate I felt the full force of misogyny. From the blunt sexism of my opponent to the trap of likeability, which seems to only ensnare women," Hillary said.

Albert Cara/Anadolu Agency via Getty Images Hillary Clinton

In last year's presidential election, Clinton said she was inspired by the diverse field of 2020 candidates in the Democratic primary but also discouraged "to hear the same familiar tropes about women candidates' speaking styles, voices, authenticity."

In September, Clinton received an honorary Doctorate of Civil Law from Oxford and, toward the end of her speech on Tuesday, she reminisced about previous visits to the campus.

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"I had just graduated from law school," she said of her first time there. "My then-boyfriend, Bill Clinton, took me to revisit his haunts. We went to University College. It was wonderful. We visited a lot of other places that were interesting. It was a walk down memory lane for him and an immediate feeling of attraction for me."

In 2014, she continued, "I sat here as a proud parent as Chelsea received her PhD in International Relations."

"The entire ceremony was in Latin, which I thought was terribly exciting," she said. "Having taken three years of Latin, I was sending a little prayer to Miss Fisher and Miss Snyder, who had been my teachers, whenever I could recognize a word."

Felix natalis, Secretary Clinton.