Inheritance isn't taxed federally unless you are talking huge dollars. The purpose of informing the IRS on deposits over 10k is to look for patterns that may show tax fraud, not occasional stuff. EDIT: thanks to the comments - I remember now it is cash deposits that have to be reported.

Over the past several years I've been involved with finalizing several family estates and never had a problem with larger transfers of funds.

EDIT:. Just a notion, first if she is writing the checks, it's not inheritance but gifts. Many older people are still under the incorrect understanding you have you can only give 10k a year without gift taxes. The level is now over 11million over her lifetime where reporting is required if over 15k in a single year. Did the checks have dates in two separate calendar years?