If any of these Forms 1099-R are for a distributions from the original IRA held by your sister-in-law, because you are not the surviving spouse of the deceased, these Forms 1099-R represent distributions that were not eligible to be rolled over. Movement of an inherited IRA to another inherited IRA for the benefit of a non-spouse beneficiary can only be done by nonreportable trustee-to-trustee transfer, not be distribution and rollover. If the money was actually moved by a proper trustee-to-trustee transfer, you must ask the custodian of your sister-in-law's IRAs to issue corrected Forms 1099-R indicating that $0 were distributed. Otherwise, if these were distributed to you and the funds came under your control, no rollover was permitted and the deposit of this money into an inherited IRA is an excess contribution.
If these are only Forms 1099-R for distributions from the IRA(s) to which the funds were moved, please answer fanfare's question asking why you believe you are being double taxed.
