On Sunday his Instagram handle, @IfJayHadInstagram, posted a tribute to Cavallari for the special occasion and the ex-NFL star's supporters were confused since he reportedly doesn't run the account.
"Happy Mother's day to all the moms. These 3 little ones picked a good one," the caption read while the photo featured Cutler's and Cavallari's three kids: Camden, 7, Jaxon, 6, and Saylor, 4.
Cavallari, 33, admitted in 2018 that she was behind the photos. "I think there needs to be a little clarification on Jay’s Instagram," she wrote at the time. "It’s not him running it. It’s me. It’s what Jay would have if he had Instagram."
A fan called Cavallari's alleged tribute to herself "gross."
"This is really gross," one person wrote. "If jay had instagram he wouldn't post this. Tell your media team this post is insensitive and disrespectful to Jay."
"Kristin, babe. We know you run this account. Happy Mother's Day though," said another person.
"YOU WON'T FOOL US KRISTIN," called out someone else.
Another fan commented, "Kristin, get off his account."
On April 26, the couple announced they were divorcing with a social media post. The two married in 2013.
"With great sadness, after 10 years together we have come to a loving conclusion to get a divorce," Cavallari and Cutler wrote. "We have nothing but love and respect for one another and are deeply grateful for the years shared, memories made, and the children we are so proud of."
Cavallari attributed the split to the two "growing apart."
She concluded: "We ask everyone to respect our privacy as we navigate this difficult time within our family."
Their split has been somewhat contentious, but a recent report said they reached a custody agreement over their kids.
The custody agreement included instructions for Mother's Day and Father's Day, which stated that the children will spend the majority of the holiday weekend with the respective celebrated parent, People magazine reported.
Fox News' Nate Day contributed to this report.