millacon

Will I be able to buy her a drink or anything else with my OBC?

My daughter will be traveling as a solo and so will I (long story) in different staterooms but have linked our accounts on the app (at least she is showing up on mine). My question is can I use OBC or another way to pay for things for both of us like excursions, spa, etc. ? Would I have to do it on board or can I send her money so she can add to her account? This is our first Princess cruise. If onboard, would I be able to use some of my OBC to pay for her tips or drinks? I have the drink package but if she wants a drink (and I don't want to lose my package by buying one for her) will they allow me to purchase a drink for her? And do you know if Princess would allow her to have a medallion for access to my room if I want her to come in as she pleases (to wait for me and such)?