First, I gathered my materials.  Washable markers, blank note cards, large scrap paper, and a baby wipe.

Then I placed Little Sister in her high chair.  (Most high chairs have a larger tray than this.  We choose to use a portable high chair at home so she is the same level as us.  It also takes up less room.)
I set down the scrap paper and then the note card.  Unfolded, it provides a larger surface for her to color.  I handed Little Sister a marker, and said the color of it as I removed the cap.  She scribbled for a bit, and then handed it back to me and received a new marker.

As soon as she lost interest we stopped.  She colored* four cards in just a few minutes.  The baby wipe quickly cleaned the marks off her high chair's tray, hands, and lips.  (Yes, she still explored the markers with her mouth, but only once!)

Each card now says, "Art by Little Sister.  Age 1 1/2."  Then I wrote a few notes to grandparents.

*Little Sister colored every single card with her left hand.  She eats most of the time with her left hand.  I suspect she will be left-handed, just like Big Sister!
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Annette {This Simple Mom}