Acrylics dry very fast, so the scope of modifying the painting by rewetting it is not possible. Oil paintings can take months to get dried up completely. Pastels run the risk of getting smudged. And if you assess from the economic point of view, watercolor is the cheapest.
Ultimately, you will use the medium you feel most comfortable in using. After you have decided on the medium, paint the loveliest picture of your mother. Take Mother's Day as the opportunity to express your creative skills and make a painting of your mother and gift her by signing your name at the corner. She will cherish that much more than you can possibly imagine.



