What are the factors used to determine suspicious circumstances in the making of a will?

In analyzing whether suspicious circumstances are in fact present here, I may consider a number of factors including: ∙ whether the will in question constituted a significant change from a former will; ∙ the extent of any physical and mental impairment of the testator around the time the will was signed; ∙ whether the will in question generally seems to make testamentary sense; ∙ the factual circumstances surrounding the making of the will; and ∙ whether a beneficiary was instrumental in the preparation of the will. Rufenack v. Hope Mission 2002 ABQB 1055 at para. 66. I will deal with the latter point when I discuss undue influence. a) Differences between the Will and the 1974 Will