RSSHe was NOT married to an Arab.
Marlo Thomas is the daughter of Danny Thomas. Danny Thomas was a Maronite Christian from Lebanon. Although the Lebanese speak Arabic, they are not Arabs. Their most recent pre-Arabic language was Aramaic, so they are Semites. Most historical Lebanese are probably descendants of Phoenicians/Canaanites with a mix of other tribes and Mediterranean peoples.
Dialects of Arabic are spoken by many ethnic groups throughout the middle east, but that does not make these other peoples Arabs. Consider that most Latin Americans speak Spanish, but that does not make them Spaniards. Likewise, most English speakers are not Anglos.
I know that Maronite and other Lebanese Christians do not consider themselves Arabs. Lebanon has more Muslims now because a huge number of Palestinians were pushed out of Palestine (there are, course, many Christian Palestinians). Palestinians, like the Lebanese, are also not Arabs. They speak Arabic now, but they were from Canaanite stock. Egyptians are not Arabs, yet they speak a dialect of Arabic. I could go on.