When Rachel Perman told her son he could celebrate his fifth birthday with a photoshoot, he obviously chose his favorite movie, "Up." Elijah, 5, loves the Pixar classic, so it was a dream come true to dress up like the characters.

When Rachel Perman told her son he could celebrate his fifth birthday with a photoshoot, he obviously chose his favorite movie, "Up."

Elijah, 5, loves the Pixar classic, so it was a dream come true to dress up like the characters.

Elijah dressed as Russell and had the idea to incorporate his 90-year-old great-grandparents as Carl and Ellie. Richard and Caroline Bain, true-life love birds, were the spitting image of the animated couple.

Perman, who is a part-time photographer, took the photos herself and posted them on Facebook, where they went viral. Elijah's twin sister, Emilee, also had a birthday photoshoot. She decided to pose with a horse dressed like a unicorn.

Perman explained on Facebook that she doesn't always post personal photos on her professional page, but these images took off on social media. She told CBS News the driving force behind the photoshoot.

"Five years ago, I was diagnosed with cancer right after my twins were born, and had fears if I would even get to see their fifth birthday," Perman told CBS News. "My oldest was 5 at the time and I hated not knowing if I would get the same time with them that I got with her."

She was sick for about a year and is now in remission. She made it to her twins' fifth birthday — something she was unsure of. So, she wanted to celebrate in a big way.