Michelle Obama celebrates Martin Luther King Jr.’s legacy on a day with dual significance.

The former first lady – who previously announced that she would not attend Donald Trump’s second inauguration on Monday, January 20 – posted a tribute for MLK Day while her husband, Barack Obamaand other former first couples piled into the US Capitol for Trump’s inauguration.

“Patron Dr. Martin Luther King Jr.’s legacy of service always inspires me,” Obama, 61, wrote in a Instagram posts on Monday morning.

She continued, “This #MLKDay, I hope you’ll join me and @WhenWeAllVote to honor Dr. King’s life and legacy by getting involved in your community. Whether you’re mentoring students at your local school or volunteering for a cause that is important to you, everything helps make a difference.”

Obama also asked his followers to share in the comments how they gave back.

A source previously told PEOPLE that the former first lady is “not one to pretend for the sake of protocol,” regarding her decision not to attend the inauguration. The Obamas previously attended Trump’s inauguration in 2017, handing over the keys to the White House after eight years.

“Her feelings about (Trump) cannot be overstated,” the source told PEOPLE. “She’s not one to put on a pleasant face and pretend for the sake of protocol.”

“Michelle doesn’t do anything because it’s expected or because it’s protocol or because of tradition,” the source continued.

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Mrs. Obama did not attend former President Jimmy Carter’s funeraleither, where she would have been seated next to President-elect Trump. At the time, her advisor attributed her unexpected absence to a scheduling conflict, stating that she was in Hawaii on an extended vacation.

Obama spent the 2024 campaign cycle voicing his concerns about Trump’s vision for America.

The source added that Trump’s history of attacking the Obama family and making disparaging comments about people of color also contributed to Michelle’s opinion of him.

“She served in the public eye and did all the public good she could during eight years as first lady,” the source said of her fulfilling her official responsibilities in 2017. “You will see her when she has a project or a cause to promote but she don’t feel the need to be a public figure anymore.”