A few of these Pokémon, as a result of new evolutions, become a part of evolutionary families with branched evolutions. Those Pokémon which evolve into a Pokémon of a previous generation, instead of from it, are specifically baby Pokémon.
Generation IV introduced the most evolutionary relatives to Pokémon from previous generations, numbering 29; Generation II introduced 19, Generation III two and Generation VI only one.
Generation V introduces none, the only generation other than Generation I which does not.