A: Bonding isn't a one-time event, it develops over weeks, months, and years. So under typical circumstances, we don't worry about bonding and attachment when there is a brief hospitalization. It's actually a good thing that your son is so attached to his grandmother -- you have help, and they will have a nice bond together. But I'm concerned that YOU feel it isn't OK. Might there be any unresolved issues between you and your mom? Or is it possible you may have some depression or other emotional issues you are struggling with that make you feel more vulnerable at this time?
Not knowing your situation fully, I can't make specific recommendations here, but you may want to consider talking with an experienced therapist who can help you sort out what sound to be difficult and confusing feelings for you. Often, just a few sessions of talk therapy provide great relief and clarity, even for situations such as these. Let us know how it goes!