The inference from all this is that we should rely on Aristotle rather than on Timaeus.
And what follows in the latter is quite peculiar. For it is foolish to suppose, as he hints, that it was improbable that the slaves of those who had been the allies of the Lacedaemonians should adopt the friendly feelings of their masters for the friends of those masters.
Men, indeed, who have once been slaves when they meet with unexpected good fortune attempt to affect and reproduce not only the likings but the friendships and relationships of their masters, taking more pains to do so than those actually connected by blood, and hope to wipe out their former inferiority and disrepute by this very effort to appear rather as descendants than as freedmen of their late masters.
Walbank Commentary