"#beyond friends are true. Love @parishilton congratulations on your new song!" Lohan wrote, referring to Hilton's new single, "B.F.A. (Best Friend's Ass)."
Lohan also started following Hilton on Instagram. It is unclear if she ever had before.
Another pic, with Lohan has since deleted, showed the actress with Hilton's sister Nicky Hilton in 2011. She captioned it with a butterfly.
Lohan and Paris' bad blood was first made public in 2006, when paparazzi filmed the heiress laughing as her friend, Brandon Davis, famously branded the actress a "fire crotch." Lohan later allegedly called Hilton the C-word on-camera, then denied saying it. During a night out with Hilton and Britney Spears, Lohan and the heiress appeared chummy when confronted together by the paparazzi.
In 2017, Lohan took to Twitter to call on "#nicegirls" Spears, Hilton and Beyoncé to attend her birthday bash on the Greek island of Myonos, where she has her own beach club.
Later in 2017, Hilton seemed to reignite her feud with Lohan after she was asked about their 2006 night out with Spears.
"It was just Brit and I out, and then she just, like, chased us to the car and got in," Hilton said. "She wasn't invited."
Last July, a video of three paparazzi clips showcasing her and Lohan's '00s feud was posted on Instagram on a Hilton fan account. Hilton commented on the post, writing "#PathologicalLiar," along with a laughing emoji.
When asked about her comment, Hilton told E! News at the time, "Just saying a fact. Fact of life."
In January, Lohan was asked about her relationship with Hilton on Andy Cohen's Radio Andy show on Sirius XM. She declined to talk about her.
How far will the women's feud go? The limit does not exist...