Can one owner rather than both owners of a property issue a claim?

[Vitamin33]

Happy New Year to All

Thank you in advance for any tips/pointers.

My friend has a letter of claim from a solicitor for breach of restrictive covenant, nuisance and trespass over changes on a small bit of land. The work carried out was in agreement with neighbours (a husband and wife) but the solicitor is only acting for the wife not the husband as well, so it appears hubby doesn't want to get involved, and that the the wife has changed her mind. Can this lady pursue the claim on her own? It's a horribly bullying letter that my friend is still trying to digest, asking for damages and for changes to be undone. PS just found out the property is owned on a 'tenants-in-common' basis. PPS just found out the breach of restrictive covenant relates to my friend's property, i.e. that he's breached his own covenant. He knows he's got to deal with that aspect (an oversight on his part), but can his neighbour's solicitor notify authorities about this and get him into troubles?

[luxardo]

yes the wife can make a claim on her own
anybody can notify authorities of anything but a solicitor wouldn't unless instructed to do so

[Vitamin33]

Again, Luxardo, a big thank you.*