Colette MacDonald's abdomen was covered by a Hilton Hotel bathmat.  The bathmat bore bloody streaks in Colette and Kimberley MacDonald's blood.  Paul Stombaugh compared the shapes of the Old Hickory knife and the ice pick to the bloody impressions on the bathmat, and concluded that the two weapons were set down and subsequently wiped on the bathmat. The opposite side of the bathmat bore bloody smudges which, according to Stombaugh, resembled handprints.  In Stombaugh's opinion, however, the potential handprints were not as clearly defined as the bloody handprints found on the blue bedsheet.  MacDonald admitted during the April 6, 1970 interview with CID investigators that he may have placed the bathmat on Colette's abdomen in order to treat her for shock.  MacDonald provided a similar explanation for why he placed his blue pajama top across Colette's chest.