What an interesting question!
I see a parallel in the following:
I want you (to be) happy and safe.
I want her (to be) arrested.
I want him (to be) living on his own in his own apartment.
It appears that "worrying" in
your example is a present participle (not a gerund) derived from a progressive
infinitive with "to be" omitted,
as is often done in elliptical phrases.
I don't know if other verbs follow this pattern ?can anyone think of