Dear, Frozen shoulder
gives acute pain
symptoms at night. There's no medicine for improving the shoulder however pain killers may give temporary relief but that will keep the shoulder frozen only. I would recommend her to take physiotherapy
especially shoulder mobilisation exercises which a therapist only can perform and it can take from 3 months to 6 months of physiotherapy for the condition to be fully cured (depends on her shoulder condition and medical history)
For other joints please get some blood tests done (like rheumatoid factor, Utica acid, ESR and CRP etc) to check out the kind of arthritis and for that you need to consult an orthopaedic.