Please make a baby Pokemon that is the baby form of both Kangaskhan and Cubone. You could get the bby by offering a Kangaskhan some sort of item (Maybe a Kangaskhan pokedoll?) to a Kangaskhan (Then the sprite would change and she’d have the pokedoll with her from then on.) It would evolve into a Kangaskhan if it is female with full happiness and into a Cubone if you give it a Kangaskhan skull.
bonus idea: If you evolve your Kangaskhan from the baby it can evolve into a new stage 2 Pokemon latter. If you evolve it to a Cubone it has unique moves.
Not a new idea, but I really like the headcanon that Cubones are baby Kangaskhan with their dead mothers skulls on their heads =]