All For Paws リトルバディ ハートビートシミュレーター

Took a bit to figure out how to slot it into the plush, but once it was in, that gentle thumping is so steady and quiet—my pup settled right beside it on the first night. I've bought a couple of these over the years and this one feels sturdier than the last, like it'll last through the chewing.

The heartbeat simulator is a nice idea, but the plastic casing feels a bit flimsy and the battery compartment is tricky to open. It works okay once you get it in the toy, though.