The JW's emphatically condemned the use of gamma globulin (IgG) in 1954 (Awake! January 8, 1954 p. 25)
Four years later, in 1958 they changed their interpretation and allowed it on the basis that it didn't nourish the body as food. (The Watchtower September 15, 1958 p. 575 --Gamma globulin is the basis for post-exposure vaccines and serums.)
Three years later, in 1961, they changed their mind again and said that any and all fractions derived from blood were forbidden (The Watchtower September 15, 1961 pp. 558,559)
Three years later, in 1964, they changed their mind again. IgG was now allowed, but under a different rationale than it had been allowed in 1958 (The Watchtower November 15, 1964 p. 682)
The position with regard to IgG has remained pretty much the same ever since and few JW's even think twice about accepting it today.
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With the foregoing in mind:
What would have been the proper course for the parent of a child with ITP, Kawasaki's syndrome, neonatal immunological deficiency syndrome, etc. during one of the windows where IgG it was forbidden?
Similarly, what would be the proper course for the parent of a child with an atypical bleeding disorder today?