Trainor posted an Instagram video of her tearful surprise, writing: "I have the best big brother in the world. @ryan.trainor surprised me with crazy Christmas decorations because he knows I'm obsessed with Christmas and lights."
In July, the 21-year-old singer revealed on Jimmy Kimmel Live that she lives with her two cats and her two brothers. Trainor told Kimmel that one of her siblings is on her payroll and was hired to videotape her life while she's on the road.
The men in Trainor's family clearly have an impact on her life. When ET spoke with her at this year's GRAMMYs, she admitted that it was her father, Gary, that told her men like curves on a woman -- which inspired her hit, "All About That Bass."
"My mom told me to always not worry about your size and be very confident," she said. "But I think that [my dad] was the one who really said, 'Don't worry, baby -- boys like booty to hold at night.' My mom's too sweet, she's too innocent."