Embodiments herein relate to a method performed by a wireless device (10) for handling neighbour relationships between radio network nodes in a wireless communication network. The wireless device (10) obtains a request from a first radio network node to provide an identity of a mobility reference signal (MRS) handler associated with one or more MRSs. Furthermore, the wireless device (10) obtains the identity of the MRS handler, which identity is in direct association with at least one MRS out of the one or more MRSs, and reports to the first radio network node, the identity of the MRS handler.