It re-opened as a luxury hotel in 1934, which changed the name to Glen O'Dee.
During part of the Second World War the hotel was requisitioned by the Army and used as billets.
In the spring of 1945 the Scottish Branch of the British Red Cross Society purchased the building from the hotel company as they were anxious to provide facilities for treating tuberculosis in ex-Service men and women.
Once the War Department had vacated the building the Red Cross returned it to its original use as a sanatorium and by December 1948 Glen O'Dee Sanatorium was ready to receive patients.
The hospital was officially opened by the Queen on 10 August 1949.
It remained one of the two Red Cross Sanatoria in Scotland (Tor-na-Dee being the other) until the mid 1950s when, the demand from the Services having dwindled, the Scottish Red Cross presented both Glen O'Dee and Tor-na-Dee to the people of Scotland.
On 1 April 1955 they were assimilated into the National Health Service.
The first female patients were admitted in 1958.
In 1960 Glen O'Dee ceased being a sanatorium and was turned into a convalescent hospital.
Apart from a brief spell during the Aberdeen typhoid epidemic of 1964 it remained so until 1990, when it became a home for the elderly with physical disabilities.
This building closed in 1998 and a new purpose built building was erected on the same site.
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