2020 through 2023 were unusually tumultuous years for children in the United States, and children's welfare was prominent in political debate. Theories in moral psychology suggest that political parties would treat concerns for children using different moral frames, and that moral conflict might drive substantial polarization in discussions about children. However, such partisan frames may still differ very little if there is limited underlying disagreement about moral issues and everyday concerns in childhood when not explicitly referencing politics. We evaluate claims of universality and division in moral language using tweets from 2019-2023 linked to U.S. voter records, focusing on expressed morality. Our results show that mentions of children by Republicans and Democrats are usually similar, differing no more than mentions by women and men, and tend to contain no large differences in accompanying moral words. To the extent that mentions of children did differ across parties, these differences were constrained to topics polarized well before the pandemic -- and slightly heightened when co-mentioned with `kids' or `children'. These topics reflected a small fraction of conversations about children. Overall, polarization of online discussion around childhood appears to reflect escalated polarization on lines of existing partisan conflicts rather than concerns originating from new concerns about the welfare of children during and after the pandemic.