Anna Duggar, wife of cheating husband Josh Duggar from "19 Kids and Counting" made her first public appearance in Amy Duggar and Dillon King's wedding on Sunday, and many noticed how she gave her best effort to put on a brave and happy face during the joyous occasion.

Josh is currently confined in the rehab facility Reformers Unanimous seeking treatment for his propensity to cheat and porn addiction, and was therefore unable to accompany Anna and their four kids to the event. Their eldest daughter Mackynzie, 5, even served as a "ringing the bells" girl during the wedding.

Despite the emotional turmoil she must be dealing with, Anna tried to be selfless and celebrate Amy's big day. "Bless her heart," a source told Entertainment Tonight. "Anna tried to put a smile on, but what it must have been like for her to be at a wedding..."

Still, Anna was all grace and composure as she wrote in her message for Amy, "So happy for you!"

According to sources, Anna smiled and made small talk with friends and family members, and even gamely posed for photos. But when the ceremony started and Amy and Dillon shared their wedding vows, Anna's mood changed and a source even claimed that she "definitely looked somber."

Anna did not stay for the reception anymore, but Amy feels grateful that she even went at all, given what she is going through.

"I gave Anna a huge hug," Amy said. "I gave my Aunt Michelle a huge hug. And I got them gifts to make them feel welcome; I gave Anna a gift card to get her nails done - she deserves to pamper herself. I gave Aunt Michelle a gift certificate to her favorite restaurant. We're really thankful they came."

Anna and her four kids Mackynzie, Michael, Marcus, and Meredith are being cared for by Josh's parents Jim Bob and Michelle as he seeks treatment. Meanwhile, the rest of the Duggar family attended and enjoyed the wedding reception.

Jessa, who is pregnant with her first child with husband Ben Seewald helped cut the cake while Josiah, who just broke up with Marjorie Jackson months ago took videos of the event. Even Jim Bob's mother Mary made a contribution by helping out several days prior in beautifying the wedding decorations.

As for the Duggars' message for their beloved niece, they wrote: "We love you Amy! God Bless you and Dillon!"