Imagine this situation...there are:

Owners (tblOwners)
Pets (tblPets, child records of tblOwners)
Medicines (tblMeds, child records of tblPets)

Owners can have multiple pets.
Pets have multiple medicines.  Easy so far.

Here's the tricky part.  The Pets can be of different species (cat,
dog, bird, snake, etc).  Depending on what the species is, I want to
determine the other data that needs to be stored for the pet.  So
instead of just height, weight, age, as fields in the pet table, I
want to see number of whiskers, declawed? if its a cat...wingspan,
beaklength, feather color if its a bird...etc for other animals.
Normally I would think because of this situation, there would have to
be a table for each type of animal.  However, all pets can have
medicines and I don't want to have several medicine tables, how can I
establish tables and relationships to have this effect?
(And for a bonus, how could I have this display on the forms so the
user could select an animal type, and the corresponding data would
appear to be entered in?)