**Exhibit 31.2**

**CERTIFICATION**

| I, Robert M. Brown,   certify that:                                                                                                                                                                                                                                                                                      |
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| 1. I have reviewed this   quarterly report on Form 10-Q of BabyUniverse, Inc.;                                                                                                                                                                                                                                           |
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| 2. Based on my knowledge,   this report does not contain any untrue statement of a material fact or omit   to state a material fact necessary to make the statements made, in light of   the circumstances under which such statements were made, not misleading with   respect to the period covered by this report;    |
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| 3. Based on my knowledge,   the financial statements, and other financial information included in this   report, fairly present in all material respects the financial condition,   results of operations and cash flows of the registrant as of, and for, the   periods presented in this report;                       |
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| 4. The registrant’s other certifying   officer(s) and I are responsible for establishing and maintaining disclosure   controls and procedures (as defined in Exchange Act Rules 13a-15(e) and   15d-15(e)) for the registrant and have:                                                                             |
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|                                                                                                                                                                                                                                                                                                                     | a) Designed such   disclosure controls and procedures, or caused such disclosure controls and   procedures to be designed under our supervision, to ensure that material   information relating to the registrant, including its consolidated   subsidiaries, is made known to us by others within those entities, particularly   during the period in which this report is being prepared; |
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|                                                                                                                                                                                                                                                                                                                     | b) Evaluated the   effectiveness of the registrant’s disclosure controls and procedures and   presented in this report our conclusions about the effectiveness of the   disclosure controls and procedures, as of the end of the period covered by   this report based on such evaluation; and |
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|                                                                                                                                                                                                                                                                                                                     | c) Disclosed in this   report any change in the registrant’s internal control over financial   reporting that occurred during the registrant’s most recent fiscal quarter   (the registrant’s fourth quarter in the case of an annual report) that has   materially affected, or is reasonably likely to materially affect, the   registrant’s internal control over financial reporting; and |
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| 5. The registrant’s other   certifying officer(s) and I have disclosed, based on our most recent   evaluation of internal control over financial reporting, to the registrant’s   auditors and the audit committee of registrant’s board of directors (or   persons performing the equivalent functions): |
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|                                                                                                                                                                                                                                                                                                                     | a) All significant   deficiencies and material weaknesses in the design or operation of internal   control over financial reporting which are reasonably likely to adversely   affect the registrant’s ability to record, process, summarize and report   financial information; and |
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|                                                                                                                                                                                                                                                                                                                     | b) Any fraud, whether or   not material, that involves management or other employees who have a   significant role in the registrant’s internal control over financial   reporting. |

 

| *Date:    November 14, 2005* |   | */s/ Robert M. Brown*     |
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|                              |   |                           |
|                              |   | *Robert M. Brown*         |
|                              |   | *Chief Financial Officer* |