What do I do if my dad becomes attracted to his caregiver?

This situation can give your Dad a lot of of pleasure, but can also go very bad indeed. It’s worth making sure that all Dad’s financial documents are in order, and when that’s done, perhaps that Dad is assessed as not being legally capaable of making new wills etc. Before then, perhaps convince Dad to put assets into a trust fund. Watch out for Viagra pills, which are not unknown in this situation. I really hope this is not the deal for you, but it is a good idea to know the worst possibilities.

I agree. My wonderful father lit up like a candle when his caregiver came and he asked for a kiss which she gave him on the cheek. It was all innocent and made his last days happy. She knew how to handle and was very professional

If she's a professional, she'll know how to handle it. However, be sure she isn't doing anything to encourage him to give her extra money or items from the house. She shouldn't be accepting any "gifts" from him.

Nothing. As long as he's keeping his hands to himself and not using lewd or inappropriate language with his caregiver, then all is well. A person is entitled to be attracted to someone as long as he looks but doesn't touch and doesn't make her feel uncomfortable in any way.