Wally West is coming home for Christmas, but when he gets there, he won't be too pleased to find that Barry Allen has usurped his spot as Joe West's son.

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Not yet Kid Flash, Joe's (Jesse L Martin) 18-year-old son will enter the picture in "Running to Stand Still." The detective will have learned of his existence from Francine, but that won't tempter his surprise when the drag racer knocks on his door.

For Wally (Keiynan Lonsdale), walking into a new family won't be easy, particularly as his mother nears the end. While he tries to fit in with Iris (Candice Patton) and Joe, the youngster will won't take kindly to the position the affable scientist already holds in their lives.

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"Wally is trying to find his place within this family, but his place is already kind of taken, in his eyes at least, by Barry," Lonsdale told Entertainment Weekly. "He isn't the biggest fan of Barry in the beginning. Obviously we know in the future and in the comics at least that they're going to be running side by side, but at this point, it's a funny sibling rivalry from Wally's end, at least."

This ill will shouldn't last too long, however. After all, Barry (Grant Gustin) is nothing if not kind.

"Barry's such a great guy," Lonsdale said. "He's such a funny, nice human that it makes the dynamic pretty entertaining."

Are you ready to meet the future Kid Flash? Catch The Flash's midseason finale this Tuesday at 8 p.m. ET on The CW.

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