Danica McKellar is 48 now but it seems she has not aged at all. The "Wonder Years" star shared a bare-faced selfie on her Instagram page Tuesday to mark her 48th birthday.

"Well hello there, 48! ❤️. Here's the obligatory #nomakeup, #nofilter shot," McKellar wrote as she shared a selfie. She smiles at the camera while lying against a pillow wearing a simple maroon sweatshirt.

McKellar, who was a Hallmark Channel mainstay before moving to the Great American Family network, added: "Thank you for all your sweet birthday messages already today! Wishing you all a beautiful 2023, and thank you so much for being on this journey with me, both with my movies on @gactv and with @mckellarmath, and of course also with my newfound faith, for which so many of you have been so encouraging!"

She stressed that a good attitude is key to maintaining a youthful look.

"If there's any secret I've found to youth, it's in the attitude... and a healthy, clean lifestyle, of course," she said. "Our minds and bodies are inextricably connected. I've found when I eat well and get enough rest and exercise, I have so much more access to that inner joy that makes life fun! And when I discipline myself to see good (and laugh at the absurdities) in the world, resisting the seduction of outrage addiction."

McKellar, who is also a mathematician, shared some tips to remain happy: "I find I'm more likely to stay in gratitude and make healthy choices...like going to bed early instead of staying up late to scroll through... all the things there are to be outraged over. 🙃 The other secret to life? Taking all that gratitude and giving back to the world in as many ways as I can. My grandmother always said, 'The way to be happy is to make other people happy.' Spread it around."

Many of the "Crown for Christmas" actress' friends and fans shared birthday wishes on social media.

"Riverdale" actress Marisol Nichols commented, "You look 20!"

Hallmark Channel's Jill Wagner wrote, "Happy bday beautiful," while Candace Cameron Bure said, "Happy birthday Danica!!!! May God bless you abundantly this new year in ways unexpected."

Last month, McKellar weighed in on Neal Bledsoe's exit from the Great American Family network following Bure's controversial "traditional marriage" statement.

"He's such a great actor and I have enjoyed working with him so much. He and I both share our love and support of the LGBT community for sure... but I don't agree with his interpretation of her comments. I just didn't see them the same way," McKellar said.

Danica McKellar in Hallmark's MatchMaker Mysteries
Danica McKellar stars in "MatchMaker Mysteries: A Fatal Romance" on Hallmark Channel and Hallmark Movies and Mysteries. Crown Media