Buy or make a matching set of light, solid colored aprons from sturdy cotton fabric. Next find quotes about cooking, mothers, family, love, etc. Using fabric markers, write the quotes on the aprons.
Choose a sturdy pair of chairs (rocking, lawn, director's, papasan, etc.) from a reputable furniture dealer OR Find used large and small chairs on craigslist or at your local Restore or thrift store. Lightly sand, then spray paint to match.
Buy or make two matching fabric covered boxes. Fill mom's box with stationery, writing tools, and stamps and the other box with colorful paper, envelopes, washable markers and assorted stickers. When mom needs to send a note, kids can busy themselves with sending one too!
Go to a bead store and make matching sets of earrings together OR if you live far away from your mom, make hers and send it along with a picture of you wearing the matching pair.
Decorate two picture frames to match (or purchase matching ones) and then put a favorite picture of you and mom together, or take a new one together just for this occasion! Here is another fun, retro idea for doing a unique matching mother-child picture gift that you could put in your frames!