Spanish citizenship with Spanish born children

Hello, I am from the UK, my wife is non-EU. She has had Spanish residency for over 5 years and is now re-newing for another 5 years, no issues here. We have 3 children, all born in Spain and holding Spanish birth certificates although they have UK passports. Does anyone know whether my wife can apply for Spanish citizenship on the grounds that she has 3 children born in Spain. Thanks....Steve