5 and half yrs old f child born of nonconsanguinous marriage maratha by caste presented with h/o vaginal bleeding intermittently every 3-4 months and lasting for about a month once started .she bleeds heavily around 15 cc per day and requires transfusion for that .this is ongoing since last three yrs i.e.from the age of 2 yrs of the child .she has recieved multiple transfusions for that and it was observed by parents that the child stops bleeding after taking the transfusion by around 7-8 days.she is investigated for the same and lh/fsh , thyroid assay are normal.x ray limbs are not s/o mc cune albright syndrome.platelet count is normal and theey are seen in clumps.pt/pttk are normal.how to investigate further