Our study is the first that aims at estimating the intra-individual effect of marital dissolution on mental health, conditional on parenthood status and age of the youngest biological child. We rely on the set point model that predicts a onlinear, homeostatic self-regulation process with an anticipatory effect and a subsequent recovery phase. Assuming heterogeneous effects, we expect both parenthood status and age of the youngest biological child grouped into five distinct categories to moderate the strength of the dissolution-health nexus. We use GSOEP data and restrict our sample to women and men who were at risk for first marital dissolution within the observational period 2002 to 2016. The dependent variable is the mental health component of the SF-12 survey instrument. We estimate distributed fixed-effects (dummy impact functions), covering the time span from three (or more) years before marital dissolution up to six (or more) years afterwards. Compared to the baseline, childless women exhibit a considerable impairment in mental health after dissolution, experiencing a slower recovery than childless men. Our most unambiguous result is the negative anticipation and a subsequent downward trajectory of mental health among mothers of infants and toddlers, whereas in the respective group of fathers we do not observe any change over time. In all other parent groups, mental health reacts mostly in a short-term manner to dissolution, except for fathers of pre- and primary school children whose mental health remains unchanged. Our study provides new evidence on mental health dynamics around marital dissolution and raises the awareness of mental distress, loneliness and potential social exclusion faced by childless and parents, in particular by lone mothers of young children.