Data validation and dates

Hi all,
This is my first post. I am trying to create a custom data validation for a spreadsheet that will do two things. First, I need it to require that the user fills in the cell above the current one so that lines are not skipped (for example I am using =LEN($J11)>0) to accomplish this). The second part is that I would like to make a data validation that would require the cell be a date. Not just the date formatting. I need to ensure that the users input an actual date. I realize that there is a data validation just for dates, but to my knowledge you cannot have two data validations in the same cell. I was thinking/hoping that there might be a way I can write a custom formula that would include both of these for validation. Any ideas? Please and Thank You

This seemed to do the trick. Thank you so much!!