Simpson had three kids, and it’s a pic of her oldest that had social media users buzzing.

“Being your mom has been the greatest joy of my life,” she said on herInstagram.

“You are my rock my soul.

Ashlee Simpson wearing a black jacket

My ride or die.

You have been the greatest blessing in life that I could have ever dreamed of.

I would not be me without you.

Ashlee Simpson and her son Bronx Wentz

Thank you for choosing me to be a mom, and YOUR mom.”

He was Ashlee Simpson’s only child with former husband and Fall Out Boy bassist Pete Wentz.

Though the couple divorced in 2011, Wentz remained in Bronx’s life, co-parenting with Ashlee.

“I think it’s important to listen and to give people balance.”

“Bronx, my stepson, is brilliant.

Ashlee and Ross also havea son, Ziggy, and a daughter, Jagger.

“I thank God every day that I get to be your mom.

Thank you for making me the luckiest.”