'This is Us': Jennifer Morrison to appear in Season 4

June 19 (UPI) -- This is Us will feature Jennifer Morrison in Season 4.

Entertainment Weekly confirmed Tuesday the 40-year-old actress will have a recurring role on the NBC series.

Sources said Morrison will have a significant role in the new season, although details on her character are being kept under wraps. Morrison will appear in multiple episodes.

Morrison celebrated her casting in a tweet Tuesday.

"THIS IS US!!!!" she wrote, adding three heart emojis. "#thisisus @nbcthisisus."

This is Us follows the Pearson family -- Jack (Milo Ventimiglia), Rebecca (Mandy Moore), Kate (Chrissy Metz), Randall (Sterling K. Brown) and Kevin (Justin Hartley) -- in multiple timelines. NBC announced the show's Season 4 premiere date Monday.

"Three cheers for the Pearsons. #ThisisUs returns Tuesday, September 24 on @NBC," the network tweeted.

NBC renewed This is Us for three more seasons in May following the show's Season 3 finale.

Morrison is known for playing Dr. Allison Cameron on House and Emma Swan on Once Upon a Time. She will appear in the upcoming films The Report and All Creatures Here Below.