Id. at 351. See also Markus v. Gross, 296 N.E.2d 505 (Mass.App. 1973) (a showing of the opportunity for undue influence without further evidence "is not enough to warrant the framing of a jury issue on that question."); Love v. Love, 370 N.E.2d 445 (Mass.App. 1977). The requirement of some evidentiary showing of a factual dispute is likewise reasonable in implementing our probate appeal statute.