Jessica Simpson's 4-Year-Old Son Debuts Shaggy Cut After Chopping Off His Long Blond Hair

Ace Knute just got his first cut!

The younger child of Jessica Simpson and husband Eric Johnson looks all 4 years of his age in a sweet photo Simpson, 37, shared to Instagram Wednesday.

Ace’s signature shoulder-length blond locks have been sheared to reveal a shorter, yet still adorably shaggy cut as the little guy wades in the water in front of a stunning mountainous landscape.

“First haircut ?? (Thanks @jessieholiday for making my stud look all grown up 😢) #ACEKNUTE,” the proud mama captioned the memory.

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It’s been an emotional milestone-laden time for the mom of two. Last week, she shared a photo of 5-year-old daughter Maxwell “Maxi” Drew, decked out in her first-day-of school best and striking a precious pose for the camera.

“KINDERGARTEN 📚😢 #MAXIDREW,” Simpson wrote alongside the snap of her mini-me.

The school year may be in full swing now, but Simpson’s little ones have some amazing summer memories to keep with them — including a Moana-themed bash the singer and fashion designer threw for Ace’s 4th birthday in June.

“May wish #4 come true my beautiful baby boy,” Simpson wrote on Instagram alongside a snap of the birthday boy surrounded by balloons and a colorful cake.