Zooey Deschanelnot only had a great time atJ.D. Scott’sHalloween wedding— but it also marked a first for the actress!

On Friday, Zooey, 39, opened up about attending the holiday-themed nuptials with J.D.’s younger brotherJonathan Scott.

In a post on Instagram, theNew Girlstar congratulated J.D., 43, and his new wifeAnnalee Belleon their wedding and expressed her happiness to have been apart of their special day alongside two photos.

The first shot saw J.D. and Annalee embracing and smiling at each other under strings of lights, about to kiss, while the second featured Zooey and Jonathan, 41, posing in theirBatman and Catwoman costumesin the same outdoor area.

“Congrats to these gorgeous and gracious love birds, I was overjoyed to celebrate such a happy union!” she added.

J.D. Scott and Annalee Belle.zooey deschanel/instagram

zooey deschanel

zooey deschanel/instagram

zooey deschanel

Deschanel’s costume also got a seal of approval from the happy couple.

“Cat-Woman! My nemesis. Damn you and your charming personality and amazing costume. Curses for sneaking onto the guest list and making my family so happy. You may have won this one but we shall meet again,” commented J.D.

Added Annalee, “We’re so so happy you were able to be there with us! Your costumes were great!”

Zooey and Jonathan —who began dating in Septemberandmade their relationship Instagram official on October 20— firstgave fans a glimpse of their Halloween-wedding attireearlier on Friday.

TheProperty Brothersstar posted several photos with his girlfriend as he showed off his metal-plated armor from head to toe, a gold utility belt and a flowing black cape. In some photos, he was seen sporting a Batman mask complete with tiny bat ears and glowing blue eyes.

Zooey kept her look a little simpler with a full-length leather bodysuit, a chunky belt and a headband with black cat ears.

Jonathan Scott and Zooey Deschanel.Courtesy Michael Wilkes

JD Scott wedding

The wedding ofthe eldest Scott brotherwas held at a private home in Las Vegas on Thursday. Guests celebrated the couple with an over-the-top, 1940s and ’50s vintage movie theatre-themed soiree. The elaborate event included a ’50s candy shoppe, absinthe fountain lounge, photo trailer, concession stands, and synchronized swimmers.

Like Jonathan and Zooey, each guest came decked out in a Halloween costume. Jonathan wore a different outfit during the ceremony, as J.D.‘sgroomsmen — five in total, including Jonathan and Drew — all dressed up in Mortal Kombat-inspired outfits to stand beside him as he said his vows.

Drew and his wife Linda Phan changed into Woody and Jessie from Toy Story for the reception.

Though the bride and groom did not dress in specific costumes, their outfits were far from traditional wedding attire. J.D. sported a rhinestone-studded suit and tie and his makeup-artist bride wore asheer, corseted wedding dress, which she paired with turquoise t-strap heels and pink-tinged hair.

JD Scott wedding

Attending the family wedding is another big step in Jonathan and Zooey’s blossoming romance.

In September, asource confirmed to PEOPLE that the pair were dating after they were seen walking hand in hand in the Los Angeles neighborhood of Silver Lake, one week after the500 Days of Summerstarannounced her splitfrom husband Jacob Pechenik.

Later that month, the two werespotted sharing several smoocheswhile seated front row during a taping ofDancing with the Stars

Eric McCandless/ABC

JONATHAN SCOTT, ZOOEY DESCHANEL

A source previously told PEOPLE that Zooey and Pechenik had been separated for several months before the announcement of their split, but that her relationship with Jonathan was “new” and that “they are having a lot of fun together.”

The following week, a differentsource told PEOPLEthat Deschanel was happy about her new romance.

“He makes her laugh and he’s so sweet to her,” the insider said, adding that after the now-couplemet on the set of James Corden’sCarpool Karaoke, “They bonded over a shared love of music. He’s very close to his family and loves children.”

source: people.com