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At a limit level, two nodes with the same predecessor at every smaller level must be equal. This is a uniqueness condition; it need not provide an upper node for every cofinal branch through the lower levels.

For infinite regular cardinals $\kappa <\lambda$, a $\lambda$-tree whose levels all have size less than $\kappa$ has a cofinal branch. At levels of cofinality $\kappa$, bound all heights distinguishing distinct predecessor chains. The Fodor lemma makes this bound constant on a stationary set; one predecessor at that height occurs stationarily often. The resulting predecessor chains agree below their common heights and unite into a branch through every level. Distinct limit-level nodes with identical predecessor chains do not affect this argument.