Will trading affect happiness?

Question

In my HG, I want to give my togepi to platinum so it will groom and become happy. But will it make the togepi sad?

Answer 1

Its happiness will get reset
Once a Pokemon is traded, its happiness goes back to its original level. This inconvenient when trying to evolve Pokemon such as Umbreon, Espeon, and of course, Togepi. However, traded Pokemon grow quicker, although sometimes refuse to obey commands.

Answer 2

yes trading will reset its happines back to its base.

Source: http://bulbapedia.bulbagarden.net/wiki/Friendship