Disclaimer: If you let me own Frozen I would reward you with thousands of mini clip epilogues and an animated short of 'We Know Better'
Hitherto
It was definitely believable to a lot of people the Elsa and Anna weren't related. From their personalities to their hair color they seemed to be different. If Anna hadn't mentioned it to him the moment they had met, he'd probably have thought that Elsa was adopted or something.
There were days like these when he saw the likeness, though.
It was another lazy summer afternoon. Elsa was dismissed from her queenly duties for the day and Anna never missed a chance to hang out with her sister so he wasn't very surprised when he was dragged off along with the infamous Snow Queen into one of the castle gardens for a 'family picnic'.
Kristoff had to admit that Anna made killer sandwiches.
He sighed contentedly and looked around where Olaf was picking dandelions with Sven. His smile widened even more when he saw Anna delicately braiding Elsa's hair. If there was one thing Anna was careful about, it was her sister.
What really surprised him, though, was the lazy smile on Elsa's face as her sister ran fingers through her hair. He rarely saw Elsa this relaxed so the sight was a bit different.
A good different, though.
His eyes softened when Anna finished fixing Elsa's hair and turned around to have her own done; the two switched positions. In that moment, what Kristoff thought was fire and ice suddenly molted itself and turned into a single element.
Their eyes both held the same delighted expression and instead of cold regality, he only saw warmth in Elsa's eyes.
Elsa held the same carefree smile that Anna always wore when she was spending time with people she loved. One corner of the lip rose higher than the other - while it looked adorable on the redhead, the blonde looked nothing short of beautiful.
The day drifted away and soon the sun had set. The group had to pack up and return to reality.
As he was helping Elsa fold the picnic blanket, he couldn't help but whisper, "You look like your sister."
And he swore that the smile Elsa had that time was the warmest he'd ever seen.