Feather was not able to make Simione leave. Not that she wasn't capable, as Simione knew she could easily make schemes to ruin her but thankfully, the rest of the Tang's—Madam Silicia and grandfather Williams disliked her so it became hard for the ballerina to infiltrate the Tang's mansion and slander Simione. The only option she could do then was pressure Lyndon who was abroad to settle the matter about Simione and make her leave the Tang's family but even such effort of her remained futile.
But she isn't helpless. If Simione thinks she can keep her hands on with Lyndon in delusion that he still loves her that's why he begged her to come back, well, she's digging her own grave. Lyndon cannot let go of her for some reasons, and for those reasons, Feather knew them well.
