For those in Christ, every day should be spent looking for ways to be a blessing to others. Kindness is part of who we are in Christ. It is a by product of emulating and being changed by Him. Kindness should be something Christians practice daily to every person we can, not just once a year or only to those we prefer to be kind towards.
Galatians 6:10 says we should favor other believers as we try to do good to all people. I believe this is meant to keep the family of believers strong and harmonious.
Galatians 5:22-23 But the fruit of the Spirit is love, joy, peace,
forbearance, kindness, goodness, faithfulness, gentleness and self-control. Against such things there is no law.
Ephesians 4:32 Be kind and compassionate to one another, forgiving each other, just as in Christ God forgave you.
Galatians 6:10
Therefore, as we have opportunity,
let us do good
to all people,
especially to those who belong to the family of believers.