Does anyone have experience with a weighted blanket to help a toddler sleep through the night?

A little background: my 3.5 year old has never slept through the night (maaaybe once or twice). It's gotten to the point that either my husband or I have to sleep with him to get him back to sleep. A large part of the issue seems to be nightmares, which I know a weighted blanket won't help. But honestly, once we are in there and can put an arm/hand on his back, often he won't even wake up again. So we are wondering if we can mimic that protected feeling maybe he won't need us as much?

I guess second question: If you don't think a weighted blanket would help, any idea what might? I am desperate to finally sleep through the night (and in the same room as DH) again!