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                                                                     EXHIBIT 3.7

                            CERTIFICATE OF OWNERSHIP

                                     MERGING

                           STERLING HOUSE CORPORATION

                                      INTO

                         ALTERRA HEALTHCARE CORPORATION

                     (Pursuant to Section 253 of the General
                 Corporation Law of Delaware and Section 17-6703
                     of the Kansas General Corporation Code)


         ALTERRA HEALTHCARE CORPORATION ("Alterra"), a corporation incorporated
on the 13th day of December, 1993, pursuant to the provisions of the General
Corporation Law of the State of Delaware does hereby certify that it owns all of
the capital stock of Sterling House Corporation ("Sterling House"), a
corporation incorporated under the laws of the State of Kansas, and that
Alterra, by a resolution of its board of directors duly adopted at a meeting
held on the 11th day of November 1999, determined to and did merge into itself
Sterling House to be effective as of December 31, 1999 which resolution is in
the following words to wit:

                  WHEREAS, Alterra lawfully owns all the outstanding capital
         stock of Sterling House Corporation, a corporation organized and
         existing under the laws of the State of Kansas ("Sterling House"); and

                  WHEREAS, Alterra desires to merge into itself Sterling House
         and to thereupon be possessed of all the estate, property, rights,
         privileges and franchises of Sterling House.

                  NOW, THEREFORE, BE IT RESOLVED, that, effective as of December
         31, 1999, Alterra merge into itself and it does hereby merge into
         itself Sterling House and assumes all of the liabilities and
         obligations of Sterling House;

                  FURTHER RESOLVED, that Alterra does hereby agree that it may
         be served with process in the State of Kansas in any proceeding for
         enforcement of any obligation of Sterling House or Alterra arising from
         the merger contemplated hereby, and Alterra does hereby irrevocably
         appoint the Secretary of State of the State of Kansas as its

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         agent to accept service of process in any such suit or proceeding and
         directs that a copy of such process be mailed to Alterra at the
         following address:

                                    Alterra Healthcare Corporation
                                    450 N. Sunnyslope Road
                                    Suite 300
                                    Brookfield, Wisconsin  53005
                                    Attention:  Chief Executive Officer

                  FURTHER RESOLVED, that the President, any Senior Vice
         President, the Secretary and any Assistant Secretary (the "Authorized
         Officers") of Alterra be, and each of them hereby is, directed to make
         and execute, under the corporate seal of Alterra, a certificate of
         ownership setting forth a copy of the resolution to merge Sterling
         House and assume its liabilities and obligations, and the date of
         adoption thereof, and to file the same in the offices of the Secretary
         of State of the State of Delaware and the Secretary of State of the
         State of Kansas, and a certified copy thereof in the office of the
         Recorder of Deeds of New Castle County; and

                  FURTHER RESOLVED, that the Authorized Officers are, and each
         of them is, duly authorized and empowered to take all action and to
         execute and deliver and to file or record, as the case may be, any and
         all such documents, agreements, instruments, certificates or
         instructions as they, or any of them, may deem necessary or advisable
         in order to carry into effect the purposes and intent of the foregoing
         resolutions or the transactions contemplated therein or thereby, as
         shall be evidenced conclusively by the taking of such actions or the
         execution and delivery and the filing and recording, as the case may
         be, of such documents, agreements, instruments, certificates or
         instructions by said Authorized Officer or Officers.

         IN WITNESS WHEREOF, Alterra has caused this Certificate of Ownership to
be signed by its duly authorized officer, the 29th day of December, 1999.



                           By: /s/ Mark W. Ohlendorf
                               ---------------------
                               Its: Senior Vice President and Asst. Secretary

Attest:

/s/ Thomas E. Komula
--------------------

Senior Vice President and  Secretary