Although a large share of parliamentarians are parents, we know little about how parenthood affects legislative activities and careers of parliamentarians. Children cost time and energy and thus may impact legislative behavior and the possibilities to excel in the legislature, e.g. by obtaining higher positions. Moreover, children may have a different impact on the parliamentary careers of mothers than fathers due to asymmetrical care responsibilities. We investigate whether parliamentarians have fewer children than their voters and show the impact of children on parliamentary careers and activities using a new dataset on Swiss national parliamentarians between 2011 and 2020. Our results reveal that there are many parents of minor children in parliament, even more mothers than fathers. In contrast to fathers, mothers are less likely to be successful when it comes to higher positions. Moreover, mothers have a lower average output in individual legislative activities than their male colleagues with or without children.