basically, reflecting on a loved one is sending positive energy, so no, i don't place a high value on receiving permission. i don't think it's necessary to do so unless you will be invoking a higher power on their behalf or doing a ritual. before i will include somebody outside of my immediate family in my healing circle's rituals, i will ask if it's ok, but mostly because i will reveal their name and condition to the rest of the circle.
edit: i'm speaking from a standpoint of merely sending energy, spellwork should never be done without permission, except in a case of self-defense. an example is: today linguistic pedants are picking on the heathens today, and i've been empathizing with them. that's energy sent. if they want it, it's available to them, otherwise, it's just so much of the universal life source.