Macaulay Culkin celebrated his 38th birthday on Sunday

Jackson, 20, paid tribute to her godfather Macaulay Culkin on Instagram over the weekend, celebrating the former child star’s 38th birthday on Sunday with a photo montage.

Alongside the series of sweet snapshots, Jackson wrote, “Happiest of birthdays mack attack, [I] love you so so dearly and keep you very close to my heart. always.”

In one picture from the group, Jackson and the former Home Alone star flashed their matching spoon tattoos. The duo got inked together last year, with a source explaining of the art to PEOPLE at the time, “The spoons are an inside joke between the two of them.”

In other pictures, Jackson, who performs in a band called The Soundflowers, and Culkin cuddled on a chair, smiled next to a drawing, and even wore matching flannels.

Culkin also got silly at the Louvre in Paris, France, with girlfriend Brenda Song, and looked serious in a suit, in the array of images.

Jackson included a throwback picture of Culkin and her late father, Michael Jackson.

PARIS JACKSON/INSTAGRAM

In January, Culkin stayed decidedly mum about his friendship with Jackson on Marc Maron’s WTF podcast. “I am close with Paris,” he started, before elaborating.

“I’m going to warn you now, I am very protective of her, so just look out,” Culkin continued. “I am a very open book when it comes to things, but like with her, she is beloved by me.”

Calling Jackson “tall and beautiful and smart,” he added, “I’m just letting you know if we want to start going down that road it’s going to be a dead-end, you know, but I mean that in the fact that I love her so much.”