In PEOPLE's exclusive sneak peek at Wednesday's episode, the newly pregnant Haley (Sarah Hyland) is worried about telling mom Claire (Julie Bown) her big news.

This Christmas Eve, Sarah Hyland’s Modern Family character Haley has something bigger than presents on her mind.

In PEOPLE’s exclusive sneak peek at Wednesday’s episode, newly pregnant Haley is worried about telling mom Claire (Julie Bowen) about her baby on the way.

“We want to be careful to do it right,” Haley tells her sister Alex (Ariel Winter).

Now you’re being careful?” Alex asks.

After revealing that her hair is going gray from the stress of keeping her sister’s secret, Alex encourages Haley and her boyfriend Dylan (Reid Ewing) to come clean — though she’s not a fan of Dylan’s idea for how to break the news to Claire.

“We hang a stocking for Grandma Claire,” Dylan suggests, “and when she goes, ‘I’m not a grandma,’ we go, ‘Tell that to Haley and my’s baby.'”

“Promise me you won’t home-school this kid,” Alex tells her sister.

Credit: ABC

Hyland had a much easier time breaking the news of Haley’s pregnancy on social media.

One day after her character’s pregnancy was revealed on the show, the actress, 27, shared a photo showing off her faux baby bump on Instagram.

“Well I guess the cat’s outta the bag!!!” she captioned the mirror selfie. “Or more like the bump’s outta the shirt!….. that was a horrible joke. I apologize.”

The actress has also recently opened up about Modern Family’s future. (It still unclear whether the ABC comedy will continue past season 10.)

“It’s going to be hard to say goodbye,” Hyland told The Hollywood Reporter.

“We’ll never have jobs as good as this job,” added her co-star Jesse Tyler Ferguson. “We love these characters so much. We love doing the show. … If we can stick around and make this last a little longer, I think we’d all like that.”

Modern Family airs Wednesdays (9 p.m. ET) on ABC.