Dental disorders can cause excessive salivation in cats. If this is a persistent problem at this point, it would be good to look for broken teeth, a trapped foreign body (caught between teeth), odontoclastic lesions small to large enamel defects right at the gumline), eosinophilic
granuloma lesions and gingivitis. Infected or damage salivary glands sometimes cause excessive salivation, as well.
Cats can have excessive salivation from infection by feline herpes virus (rhinotracheitis virus) or calicivirus. If any other signs of disease do
develop, such as fever, sneezing, eye discharges or loss of appetite they are good signs of this problem.
A good examination of the oral cavity by a VET would be the best way to start, probably.
Best to you and your little one