Eye Contact
Something I learned in the first year of postpartum doula work; you know, right after I started with the fervor of wanting to help families breastfeed, when of course several of my first families couldn't, or didn't, or struggled so much.
I attended a conference on mental health and the speaker said what builds a baby's brain is responsive eye contact. (Breast milk too, but that was not the focus.)
And ever since I have remembered that eye contact is the other breast milk for brain development. And it helped me adjust my expectations from wanting everyone to breastfeed, to wanting everyone to connect, respond, and feed their baby with love.