Billie Lourd Honors Late Mom Carrie Fisher 5 Years After Death: 'I Miss You Momby'

Billie Lourd is explaining her grieving process, five years after the death of her mom Carrie Fisher.

Fisher died at 60 on December 27, 2016, after suffering a heart attack. One day later, Fisher's mother (Lourd's grandmother) Debbie Reynolds also died; she was 84. Marking the five-year anniversary since Fisher's death a day early, Lourd shared a throwback photo on Instagram of herself as a child next to the Star Wars actress and a koala.

"People always ask me what stage of grief I'm in. And my answer is never simple. I'm in a different stage of grief in each moment of every day," said Lourd, 29. "My grief is a multi course meal with many complicated ingredients. An amuse bouche of bargaining followed by an anger appetizer with a side of depression, acceptance for the entree and of course a little denial for dessert."

"And that's how grief should be - all things all at once - actually there is no 'should' in grief - grief just is whatever it is for you and that is how it 'should be,' " she added.

Lourd also joked about why the tribute came one day early: "For anyone wondering why I'm posting this on the 26th it's the 27th here down unda (aka Tomorrowland) so what better thing to post for my Momby's Australian death anniversary (4 words I never thought I'd be putting next to each other?!?) than this picture of her and I with a koala!? sending my love to anyone out there who needs it."

She added the message "I miss you Momby" written in emojis.

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The official account for Fisher's pet dog Gary also honored her on Instagram, writing, "It's been 5 years and not a day goes by without me thinking of you. Gone but never forgotten."

In October, Lourd opened up on the podcast New Day about the grief she felt after losing her mother and grandmother. "It was brutal. It was really, really brutal, and I still hesitate and stutter because it's really hard for me," Lourd said at the time.

The Scream Queens star — who shares 15-month-old son Kingston Fisher with fiancé Austen Rydell — described her late mom and grandma as her "favorite people," adding that she misses her mom "every day."

"She was the greatest, funniest person ever," Lourd said of Fisher. "She was my best f------ friend ever. There's no one who will ever be as funny as she is. She was just— she is amazing."