Honoring "Mother" is biblical.... but any observance of a special day honoring mothers is not mentioned in the Bible as such. Mother's and women are mentioned specifically but few times in the Bible -- "Honor thy mother...", the references in Proverbs and Ecclesiastics , the text for the message described above and others that are mentioned in the prayer below.
Secular Mother's Day goes back to Greek and Roman Days. In the 1600s England observed the pagan/Christian, "Mothering Day. In America, mothers from both sides met during the Civil War. In Boston, Julia Ward Howe created a short-live Mother's Day in 1872 in connection with an anti war movement.
In the early 1880s, the Methodist Episcopal Church in Albion, Michigan set aside the second Sunday in May to recognize the special contributions of mothers. Then in 1904, Frank E. Hering, President of the Fraternal Order of Eagles, made the first known public plea for "a national day to honor our mothers". In its present form, Mother's Day was established by Anna Marie Jarvis, following the death of her mother on May 9, 1905; she campaigned to establish Mother's Day as a U.S. national, and later an international, holiday.