It's possible she might be working in a lesser-known production, or she might be using a different professional name.
To find more information, you could try:
* Searching online movie databases: Use sites like IMDb or The Movie Database (TMDb) to search for her name or any potential aliases.
* Checking local theatre listings: If she's involved in theatre, you might find her name in local listings or theatre websites.
* Using social media: Try searching for her name on platforms like Facebook, Instagram, or Twitter.
Without more information, it's difficult to determine if Gillian Tarkington has participated in any movie or television projects.