It is easier to get something done when everyone works together. Family time is better when there’s family to enjoy it, or even when it’s time to endure something (blood related or not).
Here, in today’s scripture, David says it’s like oil or ointment (soothing) that covers the body. God requires/commands that we love in unity.
Behold, how good and how pleasant it is for brethren to dwell together in unity! It is like the precious ointment upon the head, that ran down upon the beard, even Aaron’s beard: that went down to the skirts of his garments; As the dew of Hermon, and as the dew that descended upon the mountains of Zion: for there the Lord commanded the blessing, even life for evermore.
Psalms 133:1-3 KJV