This paper looks at responsive actions built with different word orders, targeting the element kyl(lä) in Finnish and küll in Estonian, two close relatives. Depending on the action sequence and syntax, kyl(lä)/küll expresses intensity or speaker certainty, thus epistemically “reinforcing” the proposition. Historically the same lexical item, even though a noun, meaning roughly ‘abundance, plentiness’ (German ‘Menge’, ‘Reichtum’), kyl(lä)/küll currently occurs in conventionalized patterns which reveal the interface of word order and social action. In both languages, the intensifying kyl(lä)/küll initiates reactive assessments. In Finnish, it is also used as an epistemic adverb that marks speaker certainty, building affirming answers in both unit-initial and unit final positions. In Estonian, the epistemic küll initially formats consoling responses, while in unit-final positions, it is a regular part of a formulaic (dis)affirmation and functions almost like a clitic.  The paper argues that word order regarding what have traditionally been seen as syntactically peripheral elements, such as adverbs and particles, can be constitutive of units implementing social actions. It suggests that the sequential analysis of action is a perfect method for revealing subtle semantic and pragmatic differences between the uses of historically close items in related languages.