Paris Hilton can't get enough of her new title -- mom -- sharing more photos of her baby boy, whom she says is her "whole heart."
The reality star/entrepreneur posted a bunch of heart-tugging pics Monday -- or as she puts it Mommy Monday -- starring newborn Phoenix Barron Hilton Reum.
Paris and hubby Carter Reum welcomed the new kid on the block back in January after struggling to get pregnant ... and keeping it a secret from virtually everyone -- even family.
Paris has been reveling in motherhood ever since... showing off baby Phoenix like every other proud mom.
A few weeks ago we got PH out in L.A. for a book signing and she told us it's like eating potato chips -- she wants more!