Snow Estheim?

[Future Esthar]

Yes but it´s out of context.
She is basically saying:
"Hey Snow,I couldn´t let you die because my mother´s heart would not enable that.That is what gave me strength"

This only mades sense if he is Hope´s big bro.

She also told him to protect Hope and smiles before falling.

Hope stinctively knows this and that´s also what makes him whine even if he isn´t conscious of this.Not just his mother´s death.