It is an extra special week for Ashlee Simpson and her family.
On Tuesday, October 29, the "Pieces of Me" singer and her husband Evan Ross — Diana Ross' son and Tracee Ellis Ross' younger brother — celebrated their youngest son Ziggy's fourth trip around the sun.
The doting parents marked their tenth wedding anniversary this year, and in addition to Ziggy, they are also parents to daughter Jagger Snow, eight, plus to Ashlee's eldest son Bronx, 15, who she shares with ex-husband Pete Wentz.
In honor of little Ziggy's special day, Ashlee took to Instagram and shared a video montage featuring photos of the birthday party, which just in time for Halloween, had everyone decked out in spooky costumes.
In the first photo, Ziggy is seen standing in front of his birthday cake, surrounded by his iconic grandmother Diana, his older siblings, and his parents.
Ashlee further shared photos of him in an adorable pirate costume, which she expertly coordinated with, plus additional photos of the family's outing to Universal's amusement park with their friends.
"Happy 4th Birthday to our amazing Ziggy!!!!!" she wrote in her caption, adding: "We love you so much!!"
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She further gushed: "You keep us all laughing, and dressing up!! I love you my silly, fun, cuddly boy, pirates forever."
Fans were then quick to take to the comments section under the post and gush over it, plus praise the "I'm Coming Out" singer's appearance, with one writing: "Queen Diana Ross being a grandma," alongside praising hands and heart-eyes emojis, as others followed suit with: "Ziggy looks so much like you, Ashlee!" and: "God bless your beautiful family always and forever," as well as: "They are so big!!"
MORE: Ashlee Simpson's son Bronx, 15, towers over her and stepdad Evan Ross in rare family outing
In addition to Ashlee's husband Evan, Ms. Ross has four other children; she shares Rhonda, 52, with Berry Gordy, Tracee, 51, and Chudney, 48, with Robert Ellis Silberstein, plus Ross, 36, and Evan, 35, with Arne Naess Jr.
MORE: Ashlee Simpson shares sweet photo of mini-me 3-year-old son Ziggy – and you can't miss his long hair
When she celebrated her milestone 80th birthday earlier this year, Ashlee took to Instagram and shared photos of her glitzy party, and a heartwarming tribute.
"Queen Mama D, Happy Birthday... What a beautiful celebration of your 80th. Thank you for being inspiring, gracious, iconic, and the most incredible grandmother and mother-in-law," she wrote in her caption at the time, adding: "We all look up to you. It doesn’t get better. Love you with all of my heart."