OMG, Ashlee Simpson and Pete Wentz’s son is so grown up now!!!

Ashlee took a moment on Instagram on Monday to pen a sweet tribute for her son Bronx Wentz in honor of his 14th birthday. Wow, time flies! Posting a sweet black-and-white picture of them, the 38-year-old singer couldn’t help but gush about her little man in the caption, saying:

“BRONX happy birthday my grown boy. Can’t believe you are 14. You are the kindest, and coolest. I am so lucky to be your mom.”

Awww! Ch-ch-check out the birthday post (below):

Wow! We can’t believe how grown up he is! He really looks a lot like his daddy, right?

Related: Watch Ashlee’s Surprise Performance Of 2004 Hit La La With Demi Lovato!

That wasn’t the only birthday post he got! His stepdad Evan Ross also celebrated the teenager on social media, writing:

“Happy Birthday BRONX love you! Best Bonus son on the planet. Lets hit these slopes real quick”

Evan also shared an adorable photo of Bronx with his and Ashlee’s 7-year-old Jagger Snow and 2-year-old Ziggy Blue on Instagram Stories. See (below):

Cute! His aunt Jessica Simpson later posted a snapshot of them smiling together next to what appeared to be a cookie cake, expressing in the caption:

“Happy 14th Birthday BX!!! I love you SO very much. You are a gift to everyone who is lucky enough know you, love you and be loved by you. Being your Aunt…has been…WILL ALWAYS BE…one of the most precious blessings of my life! Thank you for being YOU! @ashleesimpsonross you are my role model”

Clearly, Bronx was feeling the love! We hope he had an amazing birthday! Reactions, Perezcious readers? Let us know in the comments!

[Image via Ashlee Simpson/Instagram, MEGA/WENN]