We have a 15 mo old with a cold/cough. we were thinking about using vick vapor rub on his chest before he went to bed. is that okay?

If you want,but: The vapor rubs are a fall back to rather old practices done at a time when we had little to offer in treatments. Aboriginal cultures still use them, along with cupping or coin rubbing. I consider such rubs as air pollution & as likely to set off a cough as to help it. If the kid enjoys your company the process can be therapeutic, but there is no reproducible evidence that they work.