KANSAS CITY, Mo. (AP) - Investigators continue searching for a motive to help explain why Chiefs linebacker Jovan Belcher killed his girlfriend and then himself Saturday morning. They are finding out that the relationship between the two was bumpy.

Belcher and his girlfriend, 22-year-old Kasandra M. Perkins, lived apart briefly earlier this year but had gotten back together by Thanksgiving, according to a friend of Perkins.

Twenty-one-year-old Brianne York says the couple, who had a 3-month-old daughter, argued about "normal couple stuff" but that her friend was "really happy about being a mom."

The Chiefs played at home on Sunday and snapped an eight-game losing streak with a 27-21 victory over the Carolina Panthers.

Coach Romeo Crennel says playing the game was absolutely the right thing to do, no matter the outcome.

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