I think for me it is about recognising and understanding those feelings. Acknowledging what tiny Echos needed and didn't get. Empathising with that little infant.
Understanding my behaviour and feelings as I grew up, in the context of infant trauma. Knowing the impact it had on me and mourning those losses.
I cant change the things that happened to me that shouldn't have, and I cant go back in time and change the love I should have recieved and didn't, but I can have a better relationship with myself now, offer love and empathy to myself now, and feel my T's love and empathy for the part of me that holds the pain of those experiences. I can't ever make them all better, but it really helps me to understand them, and to go some way towards healing them in the safety of my relationship with T.