Emmy Rossum's Younger Co-Star Doesn't Know What a Beeper is!

Emmy Rossum can’t stop smiling while running errands solo on Monday afternoon (September 15) in Los Angeles.

The 28-year-old Shameless actress looked adorable in a black tank top, floral skirt and strappy heels.

PHOTOS: Check out the latest pics of Emmy Rossum

The day before, Emmy was a lady in red as she left a Shameless photo shoot.

That same week, Emmy shared a funny conversation she had with her co-star Emma Kenney that really showed the difference in their ages.

“This convo JUST happened. Me: Do you know what a beeper is? @EmmaRoseKenney: like the thing at restaurants that tell u when to get seated?,” she tweeted.

FYI: Emmy is wearing ASOS heels while running errands.

15+ pictures inside of Emmy Rossum running errands and leaving a birthday party…