The 20-year-old model commented on the father of three's Instagram post in honor of his and Kourtney Kardashian's daughter, Penelope's, ninth birthday and revealed a fun pastime the two like to do together.
"My life my love my everything. You have changed my life forever peep, I honestly can’t express my love for thru trying on an iPhone but with that said, I love you to much!!!!!!" Disick captioned a throwback pic of the birthday girl. "And will never stop loving you each and every day for the rest of your life and will protect you till the day I die. HAPPY BIRTHDAY PENELOPE!"
Hamlin, who has been romantically linked to 38-year-old Disick since last November, commented on the post, writing, "Little peesh 💞💞 happy birthday to the best facialist in town."
In addition to enjoying some pampering with Penelope, Hamlin has also spent some quality time with another one of her boyfriend's kids. In late June, a source told ET that the model and the businessman were spotted out to dinner with Disick's oldest son, 11-year-old Mason, at Nobu Malibu.
As for Kardashian's boyfriend, Travis Barker, he too celebrated Penelope's big day in style, gifting the little girl with her very own personalized pink drum kit. The proud mom shared videos of her little girl testing out her new present on Instagram.
"My birthday girl! My favorite girl in the entire world I am so happy and proud to be your mommy," she wrote. "I cannot believe that you are 9 🎈My life is sooooo much better because of you."