Tom Sullivan wrote a column published in Friday's Denver Post saying his son, Alex, would want him to be there.
Alex Sullivan was among 12 people killed in the July 20 attack.
Alex Sullivan's widow, Cassandra Sullivan, was among 15 relatives of the victims who said the invitation from theater owner Cinemark to attend a reopening ceremony Jan. 17 was "disgusting" and insensitive.
Tom Sullivan's column didn't criticize any of the other families for refusing to attend the ceremony.
A victim representative for the Sullivan family didn't immediately respond to an email Friday.
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