She looks through the grate, and on the other side sees a mostly empty, padded room with a mattress. The only other thing in the room is a filly sitting in the center. She has a well brushed mint colored mane that’s so long it obscures most of her body from the back. This confined pony has cream colored fur and is wearing a clean but worn sky blue hospital gown. In addition, she is hugging a penguin plushie.
The sounds Mulberry heard are definitely coming from this filly. The mare can see her talking and chuckling.
The filly hasn’t noticed Mulberry yet.