It's Hilary Duff!
The gorgeous new mom — whose son, Luca Cruz, is seven months old — posed for a quick photo before bed, tweeting, “Clean face, cozy in bed! Kept my bun in from dinner … they say in Texas the higher the hair the closer to god ;) hope it works...”
Aww, we love her natural look! And such a hard-working mama deserves to kick back and relax at night.
Did you know it was Hilary Duff? Tell us below, and then click here to play more “Guess Who?”