The grandparents were identified by CBS News as Tony and Pat Sindoni, of Berlin.
"Come with me and my ten adult cousins to surprise our grandparents by showing up one by one," Emily Sindoni captioned her 1-minute and 31-second clip.
The video had 5.7M views as of Christmas morning.
"Our favorite people in the world!" Tony says as he opens the door for Emily, the first to arrive.
Then, more come in. And each time, Emily's video flashes text over her grandmother: "She can't handle it," or, "Still can't handle it."
Each grandchild shows up with food, gifts and entertainment, which viewers felt was rather considerate.
"Please notice how they came with food and gifts and activities," one TikTok user said. "Not to burden them with feeding and entertaining them. Beautiful gestures."
Others got a kick out of Pat opening Christmas pajamas, something she says she's never had before.
The best part of all, according to another TikToker: "Money can never buy this type of happiness!"
Daily Voice has reached out to Emily Sindoni for comment.
Click here to watch the Sindoni surprise.
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