The Masked Singer judge has been married to Donnie since 2014
Jenny McCarthy marked an emotional milestone on Thursday and confessed she could barely believe it was happening.

The TV personality took to Instagram with a photo of her son, Evan, and revealed he was celebrating his 21st birthday.

Alongside the image of her only child sitting on the beach, she wrote: “Happy birthday to the most amazing, beautiful, sweetest man, my son @evanjasher I can’t believe you’re 21. How did that happen?!? I love you so much.”

Fans also wondered where the time had gone and commented: “Time goes by way to fast these days,” and, “wow, he grew up”.

It’s been a big year for Evan who has been supported by Jenny and her husband, Donnie Wahlberg as he embarks on a music career.

Evan – who was diagnosed with autism when he was three – debuted his first original song, “It Doesn’t Matter,” and he did it with the help of his famous family, including his stepdad.

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Donnie encouraged Evan to sing the lyrics himself and even got his son, Elijah, 21 – who is the frontman of the bank Pink laces – to get involved.

They then brought the song to life before enlisting Evan’s filmmaker dad, John Asher, to make the music video. Speaking of the process, Donnie – who is also a dad to Xavier, 30, told People: “It was a joy to help Evan make his song a reality. He is such an incredibly sincere young man, who really has the heart of a saint and the spirit of an artist, but none of this was handed to him — he had to put in a lot of work and prove that he was committed to the process.”

He continued: “Whether or not music is his ultimate path, the act of Evan writing and recording this song is an amazing achievement and a truly touching dedication to his favorite artist. I couldn’t be more proud of him.”

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Evan was inspired to write the song about his celebrity crush, Selena Gomez. The aspiring singer, gamer and filmmaker said: “One of the many reasons why I admire and respect Selena Gomez is her ability to be brave no matter what life throws at her.

Jenny McCarthy with her son Evan inside her home© Jenny McCarthy/Instagram
Jenny can’t believe her son is 21
“I, too, have struggled with my health and relationships, and because Selena has been so open about her struggles, it has helped me find the confidence and inner strength to get through the toughest of times.”

He continued: “I wrote this song to let her know how much I appreciate her, and I wish her all the love and happiness in the world because she deserves it.”

jenny mccarthy husband donnie wahlberg© Photo: Getty Images
Jenny and Donnie have a blended family
Jenny also shared her joy at her son’s achievement and told the outlet: “Evan has been through so much in his young life, and his passion for living and creating is such an inspiration to me.

“He is the kindest, sweetest, most loving human being on this planet, and I’m excited for what the future holds for him.”

See photos of Jenny and Donnie over the years below.