I have been on FMLA since the middle of October taking care of my mom who had cancer and just passed last Wednesday. Her funeral is this week and I will return to work next week. My paycheck today barely covered one bill let alone anything else. The money is there to give me, so that is not the problem but is it ok to ask?
Being on FMLA, you did the job that your dad would have had to hire someone for had you not been there and from what you said, it's cost you since your paycheck isn't what it usually is. You didn't say if there's any money that your mom left you but if there is of course it's ok to ask. If there isn't I'd agree with what someone above said and wait till things settle down a little bit and then broach the subject with your dad. Have a reasonable amount in mind and ask your dad if he thinks it's appropriate for you to be compensated.
I did something similar and in hind sight, I should have understood that no one knew what I was dealing with. Unless you are very clear, your Dad can not possibly know what is happening with you. Please take time to figure out what you need, what bills have piled up. Consider both what income you lost as well as what it would have cost him to hire care for your Mom. The care you provided can not have a price, but Please do sit down with him and ask for him to consider giving you a gift ... at the very least. It will be non-taxable to you if he gifts you something and a gifting strategy may be a good thing for him to consider going forward anyway.
In retrospect, my lesson from going through what you have recently experienced is that no one in my family, neither my mother, nor later my siblings felt they owed me anything. I should have set it up ... up front, but even though this is now after caring, I still think you should ask, because people just don't have any ideal all the things that have come up for you, what you gave up and how disruptive this has been and may still be going forward as you rejoin the workforce.
My best wishes to you.
Sometimes I think when it comes to money reimbursement, it depends if you are the son or if you are the daughter.
If it was a son working full-time and using FMLA to help care for an aging parent, the father would automatically help with the pay. If it was a daughter working full time and using FMLA, for some strange reason it is expected of her to come to help out, with no financial reimbursement.
As Charles1921 above had mentioned, "hint" about a loan to help tied you over, and see what your Dad will do or say.
With that said, IF your dad can financially afford to help you out and it wouldn't be a hardship for him, then ask. What have you got to loose?