Hilary Duff Celebrates Son Luca's Birthday With Sweet Message and 'Ghostbusters'-Themed Party

03/20/2017 01:20 pm EDT

Hilary Duff's little boy is growing up!

The actress' son Luca Comrie turns five years old on Monday, and Duff celebrated the milestone with a Ghostbusters-themed backyard bash on Sunday, E! News shares.

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"We're doing a backyard party, which I haven't done since he was two. It's always so much work, but I'm really excited about it," Duff shared. "I think the Ghostbusters are showing up. It's going to be like a whole thing."

"We're doing hot dogs because Slimer eats hot dogs," she continued. "His dad [Duff's ex-husband Mike Comrie] is going to be on hot dog grilling duty. We're also going to have pizza and veggie and fruit trays."

In Snapchat photos from the day, Luca can be seen donning the classic tan suit made famous by the 1985 flick and posing with his mom for a few photos as the duo sport matching Ghostbusters-inspired face paint. The party was complete with birthday cake and a visit from an Oscar Mayer Wiener food truck.

The star also shared a sweet birthday message to her son on Instagram before the festivities, posting a photo of Luca with the caption, "Hey kid.... the past 5 years have been the BEST, hardest, most blessed years of my life. I love you so much. The world is yours my love ...I hope you take it. Happy Birthday Luca Cruz."

[H/T / Snapchat / Hilary Duff]

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