in the last week we have had 3 days (not 3 days in a row) where there has been cat vomit in the house, this morning it has been in 3 different spots in the house, is it time for the vet ? problem is we have 2 cats and i don't know which cat is doing it........they both seem fine and acting normally apart from finding vomit in the house, they are both 4 years old

any advice welcome