Jessica Rodriguez’ proposal to her girlfriend, Chelsea Miller, was meticulously planned out, with friends hidden around them at the Art Institute of Chicago, video and still cameras at the ready.

What Rodriguez did not anticipate was the joyful reaction of a bystander going viral and nearly upstaging the couple.

Miller told "Us Weekly" that neither she nor Rodriguez noticed the older woman sitting on a bench nearby as the Dec. 17 proposal took place.

"I was crying and shaking and a ball of nerves," Miller said. "But later that night when we were looking at the pictures, I was, like, 'Oh, my gosh. That woman is so adorable.'"

Social media users agreed. Rodriguez’ brother, Carlos Jair, posted the image to Twitter with the caption, “My sister proposed to her GF today and look at that older woman’s reaction.” Within hours, the image was retweeted thousands of times.

As of Wednesday morning, it had been retweeted more than 111,000 times and liked more than triple that amount. Video of the proposal uploaded to YouTube the day after it took place has been viewed more than half a million times.

Scroll to the end of the story to watch the video

Rodriguez explained on Instagram that she lured Miller to the Art Institute with the promise of a gala. When they arrived, she admitted she lied about the gala.

💍 #MeetTheRodriguez  My friends were holding a sign in the gallery above that said "Chelsea Miller will you marry me?" Thousand thank yous: @hsanchezperry @lizr91 @esanchezperry & Josh #artinstituteofchicago #engagement #marriage #proposal #marryme #lgbt #sscouple #Videocomingsoon

A photo posted by Jess Rodriguez (@j.essrdgz) on

Friends held up a sign reading, “Chelsea Miller, will you marry me?” Rodriguez got down on one knee as people around them looked on.

Miller told "Us Weekly" that the love the couple has been shown is overwhelming.

"There are so many people online who are ready to throw hate at everybody, and it's so beautiful to see so much support for the (lesbian, gay, bisexual and transgender) community," Miller said. "Everybody's hearts were warmed, because she looks so purely and genuinely happy for us. So many people are saying this gives them hope and faith in humanity."

The couple plans to marry in June 2018, the magazine reported.

💍 @cnicolem_ 💕 Our little family will soon share the same last name. #MeetTheRodriguez 👩‍❤️‍👩. I proposed today with the help of some of my great friends. Video and photos soon #dogpaw #engaged #dogmom #marriageproposal #artinstitute #sscouple

A photo posted by Jess Rodriguez (@j.essrdgz) on