Who said "Be grateful for your battles—they forge your character."?

This quote is attributed to Lady Sif.

Be grateful for your battles—they forge your character. - Lady Sif

"Be grateful for your battles—they forge your character."

Lady Sif Gratitude

"I am a warrior of Asgard, and I will not falter in the face of darkness."

"Strength is not measured by the power of one's blade, but by the resolve of one's heart."

"A true friend stands beside you, not behind you."

"We are forged in battle, but refined through compassion."

"Gratitude makes life richer."

"A grateful heart is a happy heart."

"Respect those who came before us."

"Life's greatest treasures are the people we love"