reserving domain names for one of her target's 3 year old daughter.
One of the three... daughters... who are old... that the target... adopted... a year ago?
That is a very ugly and incorrect phrase. First, "3-year-old" needs hyphens when used as an adjective for "daughter". Also, leading with "one of" leads the reader into thinking something in there is going to be plural: either "daughters" (if the target had more than one 3-year-old daughter) or, more likely, "targets", which would form the possessive "targets' " (apostrophe trails the s iff the -s suffix signifies a plural). And mixing prepositional possessive phrases with bare possessives is just asking for parsing trouble.
That link-text is more readable as:
reserving domain names for the 3-year-old daughter of one of her targets.
or, the less likely:
reserving domain names for one of the 3-year-old daughters of her target.
that the target had twin girls, or, if even less likely hyphenation error was misconstrued:
reserving domain names for one of the three year-old daughters of her target.
suggesting the target had triplets, each being one year of age.
Whoever edited that submission needs remedial study.