The photo, posted by husband Derick Dillard, showed the happy couple cuddling up for the holidays.
"Jill and I wish you all a happy Thanksgiving! We are truly grateful for all the incredible people in our lives, who have blessed us so much!" Dillard captioned the picture.
But the lovely holiday message was largely lost on fans who thought they spied a possible baby bump under Jill's heavy sweater. If Jill was pregnant, this would be the couple's third child.
“Black is known to slenderize and help hide pregnancies,” wrote one follower.
“I spy a baby bump,” another added.
Some said it was unlikely that Jill was pregnant so soon after giving birth to her son Samuel four months ago via Caesarean section, however.
“She’s still recovering from her c section. Just cuz there’s a bump doesn’t mean she’s pregnant,” one person said.
Other commenters were upset Derick appeared to look carefree so soon after his firing from TLC. The network cut ties with the missionary after he tweeted repeated transphobic messages about I Am Jazz star Jazz Jennings.
"How can he stand there with a smile on his face? I'm so glad he got fired. I wish the rest of the family would pay for what they did," one person said.
"Everyone except transgender, gay, women who exercise their right to choose right?!" another chimed in.
Photo credit: Instagram/@jillmdillard