In the dark days of April, still early in the COVID-19 pandemic, a little boy's birthday trip to Disney World had to be postponed.

But luckily for 8-year-old Sam Olsen, he has an amazing big sister, 10-year-old Ella.

"She spent about six weeks planning this for him," Angela Olsen said of the Magic Kingdom-inspired day that took place in their then-home in northern Minnesota.

From four ride experiences to an ice cream cart selling Mickey Bars to the background music she played, Ella left out no detail of the perfect Disney trip.

VIDEO: Big sister creates Disney at home for little brother’s birthday
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10-year-old Ella Olson came up with the idea after her little brother’s Disney trip was canceled due to the pandemic.

But there was one key detail that made it come to life, Olsen told "Good Morning America." "Once Sam put on his Magic Band it became very real."

PHOTO: Ella and Sam Olsen.
Angela Olsen
Ella and Sam Olsen.
PHOTO: Ella and Sam Olsen.
Angela Olsen
Ella and Sam Olsen.

A highlight from the day was a cardboard box she turned into attractions. Ella, her mom said, painted each side with a different experience scene and then had a "ride" along. A video of Sam on "Splash Mountain" that his mom posted to Instagram has been viewed thousands of times.

"It's completely surprised me," Olsen told "GMA" of the attention her video has received since she posted it in September. "Ella is so glad it's brought joy to other people. She and Sam adore each other."