Peterson rejoins Vikings after attending 2-year-old son's funeral on Wednesday

Minnesota Vikings running back Adrian Peterson pauses during introductions before an NFL football game against the Carolina Panthers in Minneapolis, Sunday, Oct. 13, 2013. One of the star running back's sons, a 2-year-old in South Dakota, died Friday after an alleged attack in a child abuse case. (AP Photo/Michael Conroy) (The Associated Press)

Minnesota Vikings running back Adrian Peterson leaves the field during the first half of an NFL football game against the Carolina Panthers in Minneapolis, Sunday, Oct. 13, 2013. One of the star running back's sons, a 2-year-old in South Dakota, died Friday after an alleged attack in a child abuse case.(AP Photo/Ann Heisenfelt) (The Associated Press)

Adrian Peterson has rejoined the Minnesota Vikings after missing practice to attend the funeral for his 2-year-old son.

Peterson says he went to Sioux Falls, S.D., on Wednesday for the private service. The boy died last week in an alleged case of child abuse. Peterson says he didn't know the child was his until about two months ago and had been working with the boy's mother to support the family financially and meet the boy, whose name was Tyrese Robert Ruffin.

The first time Peterson saw the child was when he was in the hospital last Thursday. The boy died the next day.

Peterson says attending the funeral was extremely difficult. He plans to play on Monday night against the Giants.