Den. superbum seedling
 

I have a very young den. superbum. I was wondering if and how I should give it a winter rest. It is only about 4 inches tall and the stalk is very thin. I don't want to kill it.

If it's very young I would perhaps not give it a full winter rest, although cutting out fertiliser and reducing watering may help.

I was advised with Den keikis not to fully rest them the first year after they were potted up.

I have no experience with this species, but generally the winter rest is required for blooming - plants not getting the appropriate rest simply don't bloom, or produce keikis instead. So I don't think winter rest is necessary for seedlings. I haven't given rest to seedlings, but different species, so if someone else says otherwise for this one, I'd go with that ;)