Tali's best friend, big sister, and all-around hero. From helping her complete her pilgrimage, to defending her when she was on trial, and everything in between, Shepard's made a hell of an impact on Tali's life. And though the quarian admirals gave her the name vas Normandy like some kind of stigma, Tali is proud to be a part of Shepard's crew. They've been working together since the beginning, and damned if she won't stick around to see things through to the end.
Another old ally from the adventures with Saren and the geth, Kaidan is someone else Tali knows she can trust. She values his friendship and opinions, and enjoys nerding out with him about techy stuff. His omni-tool sucks, though.
Like any other member of the Normandy crew(s), Tali trusts Thane - and not just by virtue of "any friend of Shepard is a friend of mine." He's a nice guy, reliable, talented... she just wishes there was something to be done for his frog TB.
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