Phil Donahue, whose influential TV talk show aired for nearly 30 years, has died at age 88.

Donahue died Sunday night of an undisclosed illness, according to a family statement provided to ABC News by a representative for Donahue's wife of 44 years, Marlo Thomas.

The family requests in lieu of flowers that donations be made to St. Jude Children’s Research Hospital or the Phil Donahue/Notre Dame Scholarship Fund, according to the statement.

After working as a local TV reporter in his native Ohio and launching a talk show on local CBS affiliate WHIO in Dayton, he moved his "The Phil Donahue Show" to the local NBC affiliate WLWD, also in Dayton, in 1967. Three years later, it entered nationwide syndication, now titled simply "Donahue."

The show would run for 26 years in syndication, produced at NBC's 30 Rockefeller Plaza, until its last show in September 1996.

He is survived by his wife, actress Marlo Thomas, to whom he had been married for 44 years.