Her coming home was unprecedented?
Do all verbs have gerunds like "coming" in the sentence above?
Her coming home was unprecedented?
Do all verbs have gerunds like "coming" in the sentence above?
Yes. "Coming home" is a gerund phrase, which acts as a noun, and it belongs to "her". It is a somewhat uncommon or old-fashioned construction though, at least where I am from.
You could do this with pretty much any verb. "His running away was unexpected", "Its running aground was inevitable" etc.