The 27 year old actress shared a new photo on Instagram Wednesday night, plus a brief video where she shows off her baby bump.
She also joked 'Real or fake?' with a pregnant lady emoji and a tongue out emoji, with hashtags #WillAndGrace and #MeetJenny.
Lovato was wearing a low-cut dark blue dress with white polka dot, with short ruffled sleeves as she posed for selfies presumably in her Will & Grace dressing room.
She also wore large gold hoop earrings, and shared a brief video plus a few other photos with different filters on her Instagram story.
Lovato's casting was announced back in August, with the actress/singer slated to appear in a three-episode arc.
Entertainment Weekly reported in August that Lovato will portray a character named Jenny, described as a 'guarded gal who comes into the life of Will (Eric McCormack) in unexpected ways.
After the news broke, Lovato shared a number of photos with McCormack and his co-star, Debra Messing on the set.
This is the first we're learning that Lovato's Jenny character is pregnant in the show, and no further details about the character have been revealed.
This will be Lovato's first TV appearance since her two-episode arc on El Rey's From Dusk Till Dawn: The Series, in 2015.
She will next reprise her role as Mitchie Torres in the upcoming sequel Camp Rock 3, and she also has a role in Eurovision, hitting theaters next year.
Lovato is part of an all-star cast including Rachel McAdams, Will Ferrell, Dan Stevens and Pierce Brosnan, slated for release in 2020.
Lovato took to Instagram in May to reveal she had signed with manager Scooter Braun, and she teased in August that she has a new album on the way.
There is no indication when the new album she's working on will be released.
NBC hasn't revealed when the new season of Will & Grace will debut, but it has been confirmed to be the final season.
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