Pregnant Ashley Graham Shares Sweet Note for Husband Justin Ervin's Birthday: 'The Best Dad'

Ashley Graham Instagram
Ashley Graham Instagram

Ashley Graham Instagram

Ashley Graham is gushing over her husband as he celebrates another trip around the sun.

The Sports Illustrated model, 34, shared a heartfelt tribute on Instagram to her husband, Justin Ervin, for his 36th birthday.

The soon-to-be mom of three wrote a loving message to Ervin to caption the gallery of romantic photos she posted on social media. The post also included a behind-the-scenes video of Ervin photographing Graham for a nude maternity shoot.

"Happy birthday to my king, Justin. I love you more and more each day I spend with you as the world's kindest and most patient, nurturing husband," Graham wrote with the Instagram post. "Thank you for being the best dad to our boys and for aging like fine wine."

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Last week, Graham called Ervin "¾ of my heart" alongside a snap of the photographer cradling her baby bump.

Graham and Ervin share son Isaac Menelik Giovanni Ervin, 23 months. The couple announced they were expecting again in July and revealed that Graham is pregnant with twin boys in September.

Recently, Graham clapped back at an Instagram user who said that her pregnancy stretch marks could affect her modeling career.

After Graham posted a video to Instagram of herself modeling with her stretch marks visible, the social media user commented, "I had twins, but I did not get any stretch marks. I hope that does not affect your career."

Graham reposted the user's comment to her Instagram Stories along with the reply, "Gosh — hope I still have a career with my stretch marks 🙄🙄🙄."

RELATED: Pregnant Ashley Graham Shares a 'Couple of Crazy Things in My Camera Roll' on Instagram

ashley graham
ashley graham

ashley graham/instagram

She again posed with her stretch marks front and center in a nude portrait posted to Instagram earlier this month, sharing, "Justin says my stretch marks look like the tree of life."

​​In August, Graham opened up to PEOPLE about being pregnant again and said "being in control" while expecting "just gets thrown out the window."

"I learned that the hard way when I tried to control everything when I was pregnant with Isaac and I told myself that I was going to bounce right back because I was breastfeeding and everybody told me, 'Oh, if you breastfeed, you're going to lose all the weight,' " Graham said. "And I had a few honest women tell me you will never feel the same. So they were just blunt with me, and sure enough, I haven't felt the same."

"And then boom. I was like, 'Well, I just got pregnant again, so maybe I'll never feel the same, and I don't even know what I felt like before I was pregnant with Isaac anyways,' " she added.