Safety and dischardge

Hi guys,
2 posts from me this week because I'm running a bit behind schedule!!I'm currently treating a lady who has been admitted for a blood clot in her right lower leg, but has a previous left hemiplegia. Medically she is ready for d/c but when the physio r/v'd her this morning they didn't think she was safe walking independently and needed close standby assistance. When I reviewed her later in the day she still needed standby assistance but on 1 occasion when she almost lost her balance, she stopped herself, had a short rest and then started walking again. Myself and one of the other physios were discussing that perhaps she may have been this unsteady on her feet before she came into hospital but it was difficult to tell and to make things more complicated she only speaks limited english!! We'll keep reviewing her until we think she is "safe" but how long can you do that for before you decide that she may have been like that before she came in? I think it would be a good idea to talk to the family but haven't seen any of them present as yet. Any thoughts?