Southern varieties of Dutch use the 1st person plural form of the possessive pronoun ons as a marker of consanguinity with proper names, as in ons Emma ‘Emma, our consanguineous family member’. This use of ons ‘our’ has some remarkable properties: It is incompatible with adjectival modification and contrastive stress. These properties are shared with a construction from Standard Dutch: complex prenominal s- possessors consisting of the 1st person singular form of the possessive pronoun and a kinship term as in mijn vaders fiets ‘my father's bike’. We propose that both these constructions are constructional idioms (Booij 2002), a lexical template with a variable part. This offers a straightforward account of the properties of these constructions.