Rumer Willis is Darden Clarkeopening up about father Bruce Willis amid his ongoing dementia battle.

In an Instagram post on Monday, the actress, 35, said that she is "missing" her dad, 68, whose condition has continued to worsen after first being diagnosed with the disease last year.

In a photo of Bruce Willis holding Rumer Willis as a baby, she captioned the photo: "Really missing my papa today," with an emoji smiling with a single tear.

"Hugs. It's an odd kind of hard to miss someone who is still here. Dementia is a cruel beast," one user wrote in the post's comments.

In June, she shared a photo on Instagram for Father's Day of the "Die Hard" star holding her daughter, Louetta Isley, born in April.

"Seeing my father hold my daughter today was something I will treasure for the rest of my life," she captioned the photo. "His sweetness and love for her was so pure and beautiful. Papa I’m so lucky to have you and so is Lou. Thank you for being the silliest, most loving, coolest Daddio a girl could ask for. Best Girl Dad in the game…."

The post from Rumer Willis comes days after Bruce's wife, Emma Heming Willis, 45, penned an emotional tribute to her husband in a personal essay written for Maria Shriver's Sunday Paper.

Willis was diagnosed in 2022 with aphasia, which affects how a person communicates, especially using speech. In February, Willis' family announced that the condition had progressed to frontotemporal dementia.

There is no treatment or cure for the disease, which Association for Frontotemporal Degeneration CEO Susan Dickinson said could be passed on genetically in about 20-25% of people, but is also "sporadic," meaning medical professionals don’t know what causes the condition.

Bruce Willis health update:Wife Emma says it's 'hard to know' if actor understands his dementia