disjointfamilies and cofinitary groups. An infinite family A ⊆ P( ) is almostdisjoint (AD) if the intersection of any two distinct elements of A is finite. It is maximal almostdisjoint (MAD) if it is not properly included in any larger AD family or, equivalently, if given an infinite set X ⊆ …
We answer a question of Garcia-Ferreira and Hrušák by consistently constructing a MAD family maximal in the Katětov order. We also answer several questions of Garcia-Ferreira.