This isn't really a yes-no question. In some senses they are, but in other senses they aren't, so the answer depends on context. For example, a lock that only opens for Time Lord DNA would probably open for Jenny, but not River. On the other hand, River has a lot more knowledge of the heritage of Gallifrey than Jenny. Neither one owns the robes that every Time Lord has. And so on. Biologically, Jenny is the same species as the Doctor so she is Gallifreyan for certain. However, she has had none of the training normally given to Time Lords and she's never looked into the Untempered Schism. As far as we yet know, Jenny has never even traveled in time.
River is human but, because she was conceived within the space-time vortex, she has some DNA that corresponds to Time Lord DNA and gives her some of the abilities of a Time Lord. She didn't inherit that DNA from a Time Lord, she acquired it as some kind of "mutation" -- very possibly in the same way the Time Lords themselves originally acquired it. She's "the child of the TARDIS" in the sense of having been conceived in the TARDIS (on her parents' wedding night).