6 yr old female child pees in dry bath tub

I have recently taken on guardianship of a six year old female child.  I have found dried urine in the bathtub three times in the last two months.  The first time I didn't say anything...the second time I addressed it with her and she denied it...the third time I made her scrub it up.  She is the only person to use this bathroom.  I know the odor and color of human urine.....  Could she be sleep walking?  Could she be acting out?  Is making her clean it up an appropriate consequence?
The fact she is with me is obvious that her life up until now has been much less than perfect.  I realize there are problems that may need attention.  Do you think six is an age for therapy?

[babygirl6152]

May just be silliness-  

and YES this is a perfect consequence- is she ok in every other area? Obedient and respectful?

not trying in any way to relieve her of the guilt but I had a cat that would urinate in the tub if she had a urinary tract infection- she did it for days and it kept getting darker then I noticed the blood tinge and realized what was wrong. I don't know if the ceramic was cold and she liked lying in there or she just wanted me to notice- just wondering if you have a cat or dog that can get in this tub?

[margypops]

What is your relationship to this little girl,?are you the great Aunt?Yes she is probably acting out and is in need of a lot of care and love, give her plenty of positive attention, dont mention the bath tub incident any more, get her involved in sports and games and friends,how is school doing? Focus on her positive side and praise her when you see her doing something good.

[margypops]

some therapy will be a good thing sometimes.