Deacon Phillippe is all grown up!

Reese Witherspoon stepped out with her 12-year-old son in LA on Sunday, March 6 — and we can't get over how big Deacon is!

deacon phillippe getty images splash
Getty Images; Splash

Deacon in March 2007 (left) and March 2016 (right).

Reese, 39, and her ex-husband, Ryan Phillippe, 41 — who were married from 1999 until 2007 — welcomed Deacon in October 2003. They are also parents to a 16-year-old daughter, Ava Phillippe.

RELATED: Ryan Phillippe Invites Ex-Wife Reese Witherspoon to His Upcoming Wedding to Paulina Slagter!

Reese is additionally a mom to a three-year-old son, Tennessee Toth, with her current husband, Jim Toth, and Ryan has a four-year-old daughter, Kai Knapp, from a previous relationship with Alexis Knapp.

Click through the gallery below to see more celebrity kids then and now!