President Joe Biden expressed “boundless love” for his son Hunter as the younger Biden’s federal gun trial began Monday.

The rare public statement on the criminal case came as first lady Jill Biden also showed support for her son by appearing at the Delaware courtroom where jury selection began.

Hunter Biden faces three felony charges stemming from a 2018 firearm purchase. It was during a period when Hunter, now 54, has said he was struggling with drug addiction. He has pleaded not guilty to the charges.

The case represents the first prosecution in U.S. history of the child of a sitting president, and comes just days after Donald Trump was found guilty of 34 felony charges in New York City, becoming the first former president to be convicted of felony crimes.

In a statement Monday, President Biden made it clear he did not want to comment on the charges faced by his son, and that he was speaking in a personal capacity as a father.

“I am the President, but I am also a Dad,” Joe Biden said. “Jill and I love our son, and we are so proud of the man he is today. Hunter’s resilience in the face of adversity and the strength he has brought to his recovery are inspiring to us. A lot of families have loved ones who have overcome addiction and know what we mean.”

The statement continued: “As the President, I don’t and won’t comment on pending federal cases, but as a Dad, I have boundless love for my son, confidence in him, and respect for his strength. Our family has been through a lot together, and Jill and I are going to continue to be there for Hunter and our family with our love and support.”

The first lady, flanked by Secret Service agents, arrived at the Delaware courthouse about 15 minutes after her son. Hunter Biden’s sister, Ashley Biden, was also there to support him. Hunter spent the weekend with his parents at their home in Wilmington, Delaware, where the president remained until he left later Monday for a campaign event in Connecticut.

The president has spoken often about how tragedy has touched his family. His oldest son, Beau Biden, died in 2015 of brain cancer. Joe Biden’s first wife, Neilia Hunter Biden, and their 1-year-old daughter, Naomi, were killed in a car accident in 1972.

Hunter Biden is also pleading not guilty in a separate trial in California later this year over accusations that he evaded $1.4 million in taxes. Amid claims from Hunter’s attorneys that he is being unfairly targeted, a plea deal that could have avoided both cases going to court fell apart in July.

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