A 10-year-old girl complains of bleeding from the alveolar socket of the extracted 63 tooth lasting for three days. The patient has a history of prolonged bleeding after removal of primary teeth and frequent nosebleeds. Objectively: oral mucosa is pale, there are small hemorrhages. The socket of the extracted 63 tooth is filled with a big bulging clot with blood oozing from under it. Forearm skin has petechiae. What specialist should be visited in the first place?