Hilary Duff's son has accidentally given her a black eye.

Hilary Duff (c) Instagram

Hilary Duff (c) Instagram

The 30-year-old actress was left in pain when six-year-old Luca - who she has with ex-husband Mike Comrie - accidentally struck her in the face, causing a bruise to break out.

She shared a photo of the bruising on her Instagram Story and wrote: "Lukie gave me a pretty sweet black eye for the fourth!

"It was an accident but sure hurt like a muther."

The 'Younger' star - who is expecting another baby, a girl, with boyfriend Matthew Koma - later shared a video of the youngster, who wasn't enjoying his homework.

She asked Luca: "Do you love journalling in the summer time?"

He didn't answer and simply shrugged when she repeated the question, prompting Hilary to add: "I'll tell you right now, he does not."

Hilary recently revealed she's expecting a baby girl and she recently admitted she was "so excited" to learn there'll be another girl in the house.

She said: "I was so nervous beforehand because I thought for sure I was going to have a boy.

"I have a boy already - which would have been great, and I'm obsessed with Luca -but I just wanted one of each.

"It was funny that I cared so much. My sister has girls and I feel like I'm really girly. But obviously for the past six years, I've bought, like, monsters and trucks and planes. Luca is into all the boy stuff, so everything is blue and green. I was just ready for pink and purple stuff. I was so excited. It was really fun."

The former Disney star discovered she was having a girl at her Gender Reveal party which she held on Mother's Day.

Hilary said: "It was the most fun day. We had close family and friends over."