She has been wearing monthly disposable contacts for the last several months (more than 6 now I think). She is always able to have her old contact when we start using a new monthly contact. She loves getting to play with the old one! She gets a contact case, keeps it in water, carries it around, takes it in and out of liquid holding it, and just examines it. The old contact usually only lasts for one day in M's care, but she enjoys getting to handle it the way she wants to.
The other day she was putting her old contact in her doll's eye. Handling it just the way we do, and trying to insert it into her doll's eye.
Perhaps a few more months of getting older, and more practice on the doll, may result in her being able to put in her own contact!