Colin Jost's mother, Kerry Kelly, was puzzled by the name of his and Scarlett Johansson's newborn son, Cosmo. On Late Night with Seth Meyers, Colin revealed that his mother questioned if the name was final and offered alternative variations. However, after meeting people in the Italian community who had relatives named Cosmo and discovering a patron saint called Cosmos, Kerry came to accept the name. Colin and Scarlett announced the birth of their son in August, and Scarlett already has a daughter named Rose Dorothy from a previous marriage.