There are women's urinals made commercially. Men can use them fine. With some practise, most women can use a men's urinal, too. If it's just your family using it anyway, maybe they can practise in the
shower and see if it works for them. Then you can plumb the urinal to whatever hidden container you want. Or they could use those SheWee or alternate brand devices to
pee into something discreet.
I'm with Michael on the Jenkins style bucket, though. I drink three to eight litres of water a day, so I pee a lot. Often I pee right in the garden, but when only using a bucket I just add more sawdust and empty more often.