Instead of doing complex criss cross wood design, just do plain planks, stain light sandy colour and pain on a beach scene or incorporate a printed pic. Give to mom as doggie door (for keep dogs off stairs).
Adjustable Indoor Solid Wood Construction Pet Fence Gate Free Standing Dog Gate
Smart Retract ~ Retract-A-Gate - Retractable Safety Gate, Retractable Baby Gate, Retractable Dog Gate, Retractable Cat Gate or Retractable Pet Gate. An easy to use wide retractable safety gate for indoors or outdoors and certified for use at the top and b