Where can i get bars for my daughters bed?

I bought a toddler bed from goodwill because it was super cheap and in excellent condition. I didn't realize it didn't have the bars you put on to hold the mattress up. So I was wondering where to get some? I've been using some planks of wood but it sinks and she hates sleeping in it and is constantly waking up at night.
I've been searching online and don't know what these things are called so all that pops up is bed rails. Any help would be greatly appreciated.

lib.rare.ian2013-09-14T11:51:23Z

Favorite Answer

Take careful dimensions of the inside edges of the bedframe, buy a piece of 3/4" plywood at the hardware store, and ask them to cut it to size for you, making it just small enough to slip inside the frame (may cost 50cents a cut or so, for two cuts).

Thomas K2013-09-14T20:29:31Z

Use 3/4" plywood as a base. Get 6-8 small L-brackets with screws to connect the bed rails to the top surface of the plywood. Use 3-4 per side, no need at top or bottom. This will prevent the bed rails from bowing out in the middle, as they are inclined to do.

Achelios2013-09-14T22:40:40Z

why not lay a piece of plywood on top of the bed slats under the mattress

I don't see how bars would be any different than wood planks... but a piece of plywood should help