Oh yes, my daughter's favorite (she loves rabbits in general) helps her all time, even during sleep. She's role playing with the doll, as well as her imaginary friends (who also aid her, and go through similar events as she does). I suppose before she had imaginary friends, a solution as OP's makes sense.

A plushie (often a favorite) who also suffers from the same (or similar) issue creates that form of empathy/connection children require.

We got some special toys as well, for example a doll with a heartbeat which supposedly helps kids with autism (both parents in our household got the diagnosis). I don't think it works for our oldest, and for our youngest jury's out on it (he's not even 1 year old).

Suffice to say I find this a beautiful project. Thank you so much for linking to it, submitter!