Depending on your definition of "star".

If it includes only those which sustain hydrogen fusion and have a spectral class of M8 or brighter, I'd say about 10-20% chance that there may be a very dim Red Dwarf hiding somewhere we haven't properly surveyed at 3-4 lightyears or so. Within 2 LY? Not a chance.

If one starts including T- and L-dwarfs, these chances increase, but that's Brown Dwarf territory and muddling the line between planets and stars. There's certainly none within 50 000 AU, but I'd reckon the chances would be slim within 2 LY, especially for L-dwarfs. Finding a T-dwarf at 3 LY? maybe as high as 80%.