His love for me feels like spilled waterrunning back to its vessel. (7-8)
Despite the huge distance between the living and the dead, our speaker still feels his brother's love. And that love exists in a way that is very present, and immediate. But it's also a bit confusing. Using a visual image to describe a physical or emotional feeling, well, that sounds a lot like synesthesia, or a blending of the senses. Perhaps our speaker is so overwhelmed with emotion that he can only use visual imagery to describe it. He can't quite say just what he feels.
Someone tell him he should sleep now. (11, 22)
On the one hand, this is a very gentle, loving way to try and lay these thoughts of his brother to rest. He's not saying, "Quit your walking around over my head!" The way he says it shows us his real love for his brother. But on the other hand, this line also tells us that our speaker is sick and tired of his constant awareness of his brother's love (and the grief that comes with it). The dude just wants a break. He wants some peace. We can't help but wonder, though, whether if his brother did give him some peace, our speaker wouldn't be a little bit sad, even lonely.
He mends ten holes in the kneesof five pairs of boy's pants. (14-15)
This act of mending is a quiet, domestic image of a father's love for his children. Even though it's not explicitly connected to love, it carries with it a clear picture of providing and caring for his children, which sounds a lot like love to Shmoop.