With a wish, Ty gave Dustin back the ability to feel the cold, but without it being able to hurt him. Simultaneously he wished to be able to see through snow at will.
With a warm cup of coco in his hand, he walked past the cosy fire smoldering in the fireplace, and looked out the window. He sipped his drink and watched poor Dustin shivering naked outside, completely encased by snow that was translucent to Ty at the moment.
Ty then made another wish. Dustin wouldn't be able to go inside nor put on any clothing. But he would be able to move again, but wouldn't be all that strong. Breaking through loose snow would be a struggle for him.
Ty returned his vision to normal and watched as his brother slowly started to break free from the snowman. His cheeks were flush red from the cold and his naked torsow was shivering in the winter wind. His lower half was still trapped. It took him a full minute to crawl back out. His dick was so small in the cold. Ty had to laugh.
Dustin ran right away towards the door, but hit some kind of force field. He turned his attention back to Ty in the window and tried to yell, but his voice was still muted. Ty didn't fix that. Instead he made a new wish.
Behind Dustin, in the garden, the snowman pulled itself back together again and began movie towards Dustin. It wanted to put itself back together again, and Dustin was required for that. He was the missing piece.