The victims were found with their hands bound with cord. Investigators say they may have been strangled.
Harper has a criminal history, including robbery and theft.
Rose was a daycare worker and had lived in the apartment for several years.
After the family didn't show up to work and school, friends and family asked Houston police to perform what's called a welfare check.
"There didn't appear to be any signs of foul play, no forced entry into the apartment, no blood outside the apartment," said Sgt. Colin Howard with HPD. "So there was not much an officer could do at that point."
It was likely the family was already dead inside. Family members broke through the door later in the day and found the victims.
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