Is it possible to reveal the lost siblings of the Sun?
  We present the results of our numerical experiments on stellar scattering in
the galactic disc under the influence of the perturbed galactic gravitation
field connected with the spiral density waves and show that the point of view
according to which stars do not migrate far from their birthplace, in general,
is incorrect. Despite close initial locations and the same velocities after 4.6
Gyrs members of an open cluster are scattered over a very large part of the
galactic disc. If we adopt that the parental solar cluster had $\sim 10^3$
stars, it is unlikely to reveal the solar siblings within 100 pc from the Sun.
The problem stands a good chance to be solved if the cluster had $\sim 10^4$
stars.
  We also demonstrate that unbound open clusters disperse off in a short period
of time under the influence of spiral gravitation field. Their stars became a
part of the galactic disc. We have estimated typical times of the cluster
disruption in radial and azimuth directions and the corresponding diffusion
coefficients.
