When America marks the 75th anniversary of Mother's Day on May 14, many of the 145 million cards given that day may not be for mothers.

Researchers at Hallmark Cards say that with the increased number of married women in the work force many Mother's Day cards address those who care for children, including relatives, nannies and babysitters. The cards now include those for grandmothers and great-grandmothers, aunts, nieces, daughters, sisters and godmothers.Mother's Day was first proclaimed officially by President Wilson in 1914, after a persuasive letter-writing campaign by Anna M. Jarvis, an unmarried schoolteacher from Grafton, W.Va.